Updated 10/01/09

FISH PARASITES;Trematodes, Nematodes, Annelids, & Feeding Worms (Microworms, etc.) in Aquariums & Ponds (Flukes, Fish Lice and Internal Round Worms, Detritus Worms); basics, Identification, and treatment in aquarium and pond fish.

Information about non parasite DETRITUS WORMS (commonly seen when an aquarium is cleaned or in aquariums with high bio loads and is an area with much confusion especially on the internet and often mis-identified as Planaria). More about Detritus Worms further into the article.

Also many types of feeding worms; such Grindal Worms, Whiteworms, Walter Worms, Vinegar Eels, and Microworms.

TREMATODES:
(Flukes, Fish Lice)


The trematodes belong to the Animal Kingdom Phylum Platyhelminthes, the flatworms and are commonly referred to as flukes. Trematodes usually have flattened bodies, a primitive digestive system, suckers for attachment to their hosts, and are hermaphrodites (an organism that possesses both male and female sex organs). The Monogenea are the class ectoparasites that infect fish.

Internal Trematodes:

Internal Flukes generally use intermediate hosts such as snails or other mollusks. The eggs must get into water in order to hatch and be able to infect their first host, a freshwater snail. The fluke develops in the snail and then burrows out to seek the second host which is a freshwater fish. Many species of snail and fish may carry these internal flukes.
- Here is a dissected fish displaying a serious internal Trematodes infection.







GILL FLUKES:


Gill flukes (Dactylogyrus) will appear on the gill filaments as tiny dark spots 0.04-0.08in (1-2mm) long.
Gill flukes can infect freshwater and saltwater fish and are found on fish from the wild as well as farmed fish. These parasites attach to the gills of the fish and feed on mucus, epithelial cells (cells that line the inside of gills and perform the tasks of secretion, absorption, protection, and transcellular transport), and blood from the host, much of this material being produced by the fish in response to the physical injury caused by the parasites. Damage is physical and inflammatory, with secondary bacterial infections such as septicemia. Small or weak fish may die from the stress of acute infestations.

Common carriers of gill flukes include: Plecostomus, Otocinclus, Corydoras, Koi, Discus, Characins, livebearers (Poeciliidae), some tetras (Characins) and Barbs (Cyprinidae), and Elephant Nose (Gnathonemus petersi).

For more about Monogeneans Flukes, which are a group of parasites best described as flatworms but are now considered a different class from Trematodes, please see these articles:
*Monogenean Parasites, Marine Fish
*Monogenean Parasites in Fish

FISH LICE (Argulus):

These are often round, flat and green.

They are similar in treatment to flukes and anchor worms. These can be physically removed with tweezers, and then the wound treated with Mebromin, hydrogen peroxide or even Neosporin followed by a 30 minute Methylene Blue bath


NEMATODES:
(Round Worms)


Also known as Roundworms are a very common phyla of animals of which there are many parasitic forms. Nematodes are one of the simplest animal groups to have a complete digestive system, with a separate orifice for food intake and waste excretion unlike the Trematodes mentioned above. Reproduction is usually sexual and males are usually smaller than females. Parasitic Nematodes can have quite complicated life cycles, moving between several different hosts or even locations in the host's body.

If the Nematode has a direct life cycle, then it does not need an intermediate host and infection can spread directly from one fish to another by means of a fish ingesting of eggs or larvae.

If the Nematode has an indirect life cycle the nematode eggs or larvae enter an invertebrate intermediate host (such as copepod, tubiflex worm, or insect larva) or a fish intermediate host (these fish are then consumed by larger carnivorous fish) prior to being eaten by or entering the final host fish.

Indications (Diagnosis) of Nematode Infestation:
A method of diagnosing a nematode problem is generally just a guess. When a fish is eating well yet is still not putting on weight, an intestinal infestation may be suspected. This is particularly plausible when a fish is eating regularly yet continues to lose weight, metabolizing body musculature to stay alive. This is usually seen as thinning along the back on either side of the dorsal fin. This often results in a well-fed fish starving to death.
White feces can also be an identification tool, however this can be misleading as to a true Nematode (worm) infestation, as long thin white feces is more often an indicator of a bacterial infection; generally Aeromonas. This can also be an indicator of a combination bacterial (again Aeromonas) and protozoan Flagellate infection, usually Hexamita.
Loss of appetite along with the other mentioned symptoms (such as thick white feces, along with some bloating on one side or both of the fish) can also be an indicator of a Nematode infection, especially a Eustrongylid nematode infestation.

Generally a more positive identification of internal Nematodes is a thread like worm protruding from the anus.

True identification begins with a microscope. Nematodes are smooth, cylindrical, relatively long worms, which distinguishes them from the flatter, segmented tapeworms and from the wider and shorter Monogenea Flukes.

Here is a list of some other general symptoms of nematode infections (besides the above already mentioned symptoms):
• Body Hemorrhaging
• Lumps or nodules on outer body (epidermis)
• Bloated abdomen (the fish may continue to eat or show otherwise normal behavior)
• Cysts, Inflammation, or Granulomas

A Few Common Nematodes:

Capillari is probably the most common nematode due to the relatively non-complex life cycle and ease of transmission, as Capillaria spread from one fish to another by ingestion of infective larvae that lives in the intestines of cichlids such as (angelfish and discus),, gouramis, tetras, cyprinids (and other fish as well). Symptoms common to this particular nematode includes a bulge in the lower abdomen near the vent, or Capillari worms protruding from the anus.

Eustrongylid nematodes are found in muscle within the body cavity or encapsulated on the liver and other organs. These nematodes can affect a number of different species such guppies, gar, danios, angelfish and other cichlids. Affected fish typically have bloated abdomens (similar to dropsy of bacterial origin), as these nematodes often migrate into the body cavity and can be quite large. Unfortunately the treatment of these Nematodes usually fails due to the location of the larvae within the coelomic cavity or in the muscle of the fish (which is often misdiagnosed as bacterial Dropsy leading to the statements that “Dropsy is un-treatable”)

Camallanus Nematodes infect the gastrointestinal tract of live-bearers, cichlids and other species of freshwater fish. Usually, the first indication of infection is a red worm extending from the anus of a fish (sometimes mistaken for feces)

TREATMENTS for internal Trematodes and Nematodes:

*Metronidazole

*Jungle Internal Anti-Parasite

*Jungle Parasite Clear

*Levamisol (most commonly available as Levamisol HCL which is slightly diluted of the active ingredient of Levimisol).
See this article for use: Aquatic Medications #3; chemical and parasite treatments
Treat with Levimisol once followed by a water change and treatment in 5-7 days. Treat a third time after 1-2 weeks following the second treatment.

*Piperazine

*Combinations such as the above mentioned Jungle Parasite Guard that have Metronidazole as an ingredient as this medication is often effective for secondary bacterial infections such as Aeromonas and even better for possible Hexamita infestations of the gut such as may be witnessed in a white feces diagnosis where the aquarist is unsure of whether this is a worm or Aeromonas/Hexamita infection.

Treatments for external Flukes:
*Clout

*Trichlorfon

*Potassium Permanganate

*Jungle Parasite Clear (this can be used for internal parasites as well)

For BOTH Internal and External Parasite Treatment
Medicated 30 minute baths using Methylene Blue, Aquarium Salts, as well as an antibiotic such as Metronidazole or Kananmycin (generally Metronidazole) at double normal recommended tank strength; This will aid in absorption of medications and osmoregulation that is VERY important, especially with internal parasite infestations which are difficult to treat even with strong medications. Methylene Blue will be absorbed and aid in oxygen delivery although it is only mildly effective against the parasites, but aids in the fish’ general health. Salt is advised not only in the baths at 1-2 teaspoons per gallon, but also in the display or quarantine tank at 1 teaspoon per gallon to 1 tablespoon per 5 gallons as this will also aid in mucous generation and the movement of fluids inside the body cavity (osmoregulation).
Correct Calcium Levels are also important for osmoregulation that will aid the fish in “battling” a parasite infestation (especially internal).
See this article for more about medicated baths:
“Aquarium Disease Prevention; Section 9”

Prevention is the BEST treatment for Nematodes and Flukes, especially Internal Nematodes
This is accomplished by regular water changes, the purchase of fish from a known quality resource, removal of the final host (in the case of Eustrongylid nematodes; birds and pond sanitation), or any intermediate hosts (tubiflex worms or other oligochaetes).

It is noteworthy that many (if not most) fish farms are located OUTDOORS, so the spread of nematodes via intermediate and finals hosts is easier than one may think, so again knowing your source for your pet fish is very helpful as often many internal nematodes will not show symptoms in fish for over 30 days after arrival in your aquarium.

A final note as to treatment of nematodes in particular is that nematode infestations are generally internal making treatment and medication “delivery” very difficult, even more so with Eustrongylid nematodes since they are found in even more difficult to deliver mediation internal body locations. My point here is to point out that hopefully one can start treatment early or prevent an infestation altogether, however from my experience this is not a “real world” expectation as I have often failed myself to detect and treat with success (assuming it being treatable in the first place), so one should not be too hard on failures in treating internal Nematodes, as I have had my share of both successes and failures even under the good care.

References:
University of Florida; Nematode Infections in Fish
University of Florida; Fish Disease Diagnostic Laboratory


Annelids “Segmented Worms” - Including:
DETRITUS WORMS

The annelids are the phylum of segmented worms which includes earthworms. Most annelids are NOT purely aquatic in fresh water; the annelids found in freshwater are all oligochaetes (which means "few-bristled") and are not very important in the freshwater ecology as are their marine cousins, the polychaetes (which means "multi-bristled"), are in marine environments.
All the oligochaete worms are hermaphrodites (an organism that posses both male and female genitalia). Many are nearly microscopic too

Detritus Worms (from the group of worms called Oligochaetes, sub group naidid worms) are often misidentified in the aquarium hobby as Planaria without close inspection by many internet articles such as about.com.
Many of these worms are accidentally introduced by live plants, gravel (especially in the case of common Detritus Worms) live fish foods, and even brought in with fish transfers.
(Click picture to enlarge)
Many not familiar with Detritus worms will label these as everything form midge larvae, Planaria to baby earthworms, of which none is true. They are very common and most often seen during vacuuming and other cleaning procedures.
These worms generally are not a problem often go un-noticed living in the gravel aiding in breakdown of wastes, however high numbers of particular species can indicate low oxygen levels, cloudy water, poor Redox and low filter productivity, which very often suggests some degree of pollution caused by poor cleaning procedures, over crowding, over feeding and poor filtration. When the population explodes these worms often leave the gravel and cling to the sides, usually close to the surface as oxygen depletion due to the cumulative affects of increased organic mulm (often resulting to pH.KH drops, higher nitrates, poor Redox Balance), cloudy water and simply too many Detritus worms drives them from the oxygen poor gravel.

Please reference these sources for even more identification (and further information so as to dispel the internet aquarium myth that these are Planaria):
Detritus Worms/Planaria
Aquatic Life: Worms ,
Oligochaeta Worms
Aquatic Worms

“Detritus Worms" include these:

As stated earlier, control of these detritus (composting) worms is brought about by good vacuuming procedures, proper feeding, good filtration, lowering bio load, and addition of fish that will eat these.

This is a Planaria (a flat worm, not an Annelid)!
(click to enlarge)








WORMS USED AS FISH FOOD

Annelids:

Whiteworms (Enchytraeus albidus):

These are worms commonly used in feeding for larger fish; for instance, Gouramis and Cory cats love Whiteworms. Microworms (which are Nematodes not Annelids as are Whiteworms) are used for fry.
What we typically refer to as a "white worm" in the aquarium hobby is a segmented round worms (Annelids) that are closely related to the earthworm from the family enchytraeids. Whiteworms are an excellent food source for many amphibians and other aquatic creatures.
These worms can reach over 1 cm or more long. They are NOT a parasite danger to fish or other inhabitants of aquariums and are often seen wiggling up the sides or even at the surface. Whiteworms are basically a worm of de-composition and can multiply rapidly when over feeding is a problem. At this point the biggest danger is oxygen depletion from over population of these worms and a good vacuuming is in order. Many a customer has called or written me about these worms worrying that they have a parasite problem when in reality these worms are good for composting and are at worst an indicator of too much decomposing food and other organic debris.

Grindal worms
A smaller version of White Worms are the popular Grindal Worms (which are also Annelids) often cultured as fish food (and named for a Swedish Aquarist).









Nematodes

MicroWorms:
All the worms that fall under the popular term of Microworms are Nematodes (roundworms) and include Vinegar Eels, and Walter Worms.
Microworms (Panagrellus Redivivus) are non parasitic and small (0.5 - 1.5 mm.) worms, which make excellent supplementary live food for fry which are either too big for infusoria or have outgrown the infusoria stage.

Walter worms:
Walter Worms are about half the size of the Microworm. These are recommended for feeding the very smallest fry. Walter worms generally live in the water longer than the Microworm.

For home grown Micro worms (Walter Worms) as well as Vinegar Eels, this is healthy source (the microworms are gut loaded with Spirulina): Over A Copper Moon Betta; Feeding Supplies




Vinegar Eels also a nematode are readily cultured in large numbers, provided certain procedures are followed. These worms (also nematodes) are a little smaller than micro-worms, a great size for most baby fish. The worms must be grown in natural cider vinegar that has not been chemically treated to inhibit the growth of bacteria or yeast upon which the worms feed. Advantages of Vinegar eels is they do not breath oxygen so don't create any problems in the fish tank, live a long time in the aquarium, and swim in the water column and stay towards the surface.

References:
The Worms
Vinegar Eels
Whiteworms
Microworms (Panagrellus redivivus)
Diagnosis of Fish Poop
Introduction to Freshwater Fish Parasites:

AQUARIUM REPAIR & SILICONE APPLICATIONS; What Silicone to use and what not to use, Aquarium Repair (& leak identification), Aquarium construction.
Updated 7/09/09

*Also how to use silicone to repair an aquarium (three different applications)
*DIY Aquarium Glass Thickness recommendations.
*YouTube Video demonstrating application of silicone for aquarium crack and hinge repair


SILCONE BASICS:

Silicone rubber is a unique synthetic elastomer made from a cross-linked polymer which is reinforced with silica. Its characteristics are such that it provides a balance of mechanical and chemical properties useful for bonding glass aquariums (not acrylic).
The basic formula is: Me3SiO(SiMe2O)nSiMe3

RTV Silicones are the silicones commonly used for glass construction and is often sold in Home Improvement and Pet Stores (or online)
RTV Silicones consist of polydialkylsiloxane with terminal hydroxyl groups (groups made up of an oxygen atom and a hydrogen atom connected by a covalent bond), which are reacted with organosilicon (chemical compounds containing carbon silicon bonds) cross-linking agents. This operation is carried out in a moisture-free environment and results in the formation of a tetrafunctional structure (A chemical structure that possesses four highly reactive sites). Curing takes place when materials are exposed to moisture. Atmospheric moisture is sufficient to trigger the reaction, and thickness should be limited if only one side is exposed to the moisture source. Curing is also relatively slow, reliant on moisture ingress into the polymer which produces Acetic Acid vapors.

Different formulas and (combined with temperature and outside humidity) will affect cure time. Dow Corning and GE have proprietary formulas (although both are packaged under other brands such as DAP & All Glass Aquarium) that cure at an even slow rate as compared to some cheaper formulas, especially used in construction where this is not an important factor. This however is important for aquariums to have an even and slow cure time as I have used 100% silicones such as CRL that would cure too quickly resulting in a less than desirable bond.
Also some formulas such as GE Silicon II have a mildew inhibitor (which would be toxic to the fish).

100% RTV Silicone Rubber Sealant produces a flexible, durable weather resistant seal between similar and dissimilar materials; RTV Silicone provides excellent adhesion to tile, glass, porcelain, ceramic, fiberglass, non-oily woods, plaster, painted surfaces, metal, many plastics, and rubber. It will withstand temperature extremes from -60°F. to +450°F. and is waterproof for freshwater or saltwater use.

It is noteworthy that plastic (which is made from oil) is not mentioned. RTV silicone is not useful for bonding acrylic aquariums and the oils within acrylic will eventually cause peeling away (lack of adhesion).
The bottom line is do NOT use silicone for repair of Acrylic/Plexiglass aquariums (or other acrylic applications)!

For Plexiglass/Acrylic aquariums you would need to use Plexiglass or PVC Cement (Glue) which works by “melting” the Plexiglass panels together. The is best applied with a needle applicator between the Plexiglass panels along with applying pressure. Silicone is often used after initial Plexiglass construction to provide more water tight seal along the seams of a Plexiglass/Acrylic aquarium, but this will peal after time (it can be re-applied) and provides NO strength for the actual plexiglass panels.
Silicone can also be used to form a seal where water pressure will push the glass panel against a surface that it would otherwise would not adhere well to (although once pressure is removed after initial filling, the silicone will likely not “seat” again in such an application where silicone does not properly bond).


AQUARIUM APPLICATIONS:

RTV Silicones are useful in the construction of glass aquariums and sealing the joints in DIY wooden aquariums. Silicone is NOT useful for acrylic aquariums as it will peel away over time due to the inherent oils in plastics.
Not all silicone formulas are the same, as stated earlier, Dow Corning and GE produce a RTV silicone that cures at an even and slow rate necessary for aquariums. Why is this important? Too fast a cure will not allow proper surface adhesion especially in important seams. It is also hard to work with in building aquariums and the person needs to work very quickly (usually too quickly) for proper aquarium construction.

Also you want to purchase pure 100% RTV Silicone as many (including ones produced by Dow Corning) have other ingredients for different applications such as fiberglass.

A good example of a silicone you do NOT want to purchase is Dow Corning Marine Sealant which I have actually seen recommended for aquariums! This product is great for fiberglass hulls of boats however it lacks the proper strength for aquariums due to added ingredients that allow for adhesion to plastic.






AQUARIUM REPAIR;

With a good silicone, you can perform a few repairs yourself.

The picture/diagram to the left shows what to basically to look for as to silicone in the important joint where two glass panels meet. This is where most of the strength is obtained from the silicone. If the silicone is missing or pulled away (as can be easily observed by looking through the glass at each joint to see if air or water is present in place of silicone), you may need to repair this. The silicone in the inside corner gives added strength and small leak protection, but is not as important for aquarium strength as the silicone in the joint. This is also important that braces (if your aquarium has a brace) have this silicone as well.
(please click the picture for a better view

Small Leak Identification:

Often small leaks are the most difficult to find (identify the source of the leak so as to repair). I have been called out by a client who thought that their tank had a leak on the bottom (which would require a strip down of the tank and stripping of silicone and reapplication), only to find that the aquarium actually was only seeping water from the top (often under the trim) and this small bead of water would run down the side seem in a manner that went unseen. This type of leak can be found more easily by gently running a paper towel along the sides to look for trace amounts of water which the paper towel would quickly find.

If this is your leak, this could be from the trim (which is often a plastic material and does not adhere to the silicone as well and can often be repaired by simply lowering your water a few inches and stripping the silicone around the trim and then replacing this silicone. Sometimes simply adding silicone in gaps in the trim or even lowering water level or reducing condensation of water on the glass top which may find its way around top gaps in the aquarium and then to the bottom of the aquarium (often resulting in a wet stand or similar condition)

For an older tank that is starting to leak (no broken glass), this can be repaired following these basic steps:
[1] Empty aquarium
[2] Remove ALL old silicone with a razor blade (I prefer a single edge razor blade, see picture to the right)
[3] Clean and prepare surface with fine sandpaper.
[4] Make sure all surfaces are dry.
[5] Apply silicone (a caulking gun works best), making .5 (or smaller) cm. bead in the inside edges.
[6] Tighten all outside corners with strong reinforced dust tape. For tanks over 75 gallons I recommend wooden clamps.
[7] Immediately uses your index finger to smooth ALL inside edge beads into a smooth surface, quickly wiping away excess silicone.
[8] Your repair is complete in 48 hours.

For non structural corner chips:
[1] Drain aquarium down to the area of the chip.
[2] Inspect/ clean/ repair the inside area in needed.
[3] Clean out broken glass on the outside chip area
[4] Carefully clean out broken glass (gloves are recommended), a razor blade followed by fine sand paper works best.
[5] Inject new silicone followed immediately by a piece of glass that fits reasonably well into this chip.
[6] Add more silicone if necessary.
[7] Smooth repair and add a piece of wax paper (or similar waxy or mildly oily band aid), followed immediately by strong reinforced duct tape to hold this repair in place.
[8] This “band aid” can be removed in 24 to 48 hours and the aquarium re filled.

For broken plastic hinges:
[1] Remove old hinge
[2] Place both pieces of glass on a firm level surface
[3] Run a .5 cm bead of silicone carefully down the area where both pieces of glass come together.
[4] Immediately, using your index and middle finger, run these fingers over the top of this silicone bead forming sharp peak of silicone between both pieces of glass. Remove excess. Bare hands (fingers) work best as the oils present repel the silicone from adhering too much to your fingers. The silicone should look sort of like this after finished: /\
[5] After 24 to 48 hours your new and more durable hinge is ready.

For MINOR cracks
[1] Clean the area on BOTH side of the crack thoroughly with a razor blade (so solvents)
[2] Apply bead of silicone as described above and in the video below forming a ridge with your fingers evenly along the crack (adding a plate of glass on the inside side of the crack will greatly increase strength). Flip the aquarium and repeat on the other side.
[3] Allow at least 24 hours to dry, allow 48 hours is better.
[4] This repair is ONLY recommended for aquariums under 10 gallons with single cracks, generally on the bottom.

For MAJOR cracks (only single cracks, not “spider” cracks)
For larger aquariums with single cracks I recommend adding a plate of glass to the inside of the crack repair in step #2. This plate need only cover the crack plus an inch or two, not the full bottom or side (although that would certainly be better yet).
I generally do not recommend this repair for tanks over 100 gallons, although I have cut glass panels to fit over the entire bottom without replacing the old cracked panel for larger aquariums or multi cracked smaller aquariums.
Otherwise I STRONGLY recommend replacing the glass panel.

Here is a YouTube Video we made for aquarium crack and hinge repair (it also shows how to correctly apply silicone and cut glass)


FOR DIY AQUARIUMS
(or simply what to look for in a new glass tank):

Recommended Glass thicknesses:
(Length x Height x Width)

2 x 1 x 1 = 5mm glass
2 x 1 x 1.5 = 6 mm glass
2 x 1.5 x 1.5 = 8 mm glass
2.5 x 2 x 2 = 10 mm glass
3 x1 x 1 = 6 mm glass
3 x 1.5 x 1.5 = 8mm glass
3 x 2 x 2 = 12 mm glass
4 x 1.5 x 1.5 = 10mm glass
4 x 2 x 2 = 12 mm glass
6 x any size x 2 feet max. = 12 mm glass

Please note that the formula for gallon calculations is L x H x W divided by 231 = Gallons. Multiply this by 3.785 for liters.
I do NOT recommend a glass aquarium over 250 -300 gallons!

Trim
• Please keep in mind that when either building or purchasing a glass aquarium, the thickness of the glass (which should be float glass), along with the type of silicone used, and finally construction methods are what will basically determine the quality of the finished aquarium.
The trim (which is generally plastic) offers LITTLE support other than providing a “cushion” between the bottom glass and stand and as well a “convenient” way to place the lid, lights, etc., on top. Of coarse the trim does certainly add to the attractiveness, but as someone that has worked with high end aquarium manufacturers and built/repaired many myself, I can tell the reader here from an experience that the trim offers little in support and if it is necessary for support, you have a dangerously poorly built aquarium!
As well, I have removed trim from many tanks (including large ones) and filled them with water with no difference other than the unattractive aspect.



SUMMARY:



Can you easily purchase the proper silicone at a Home Improvement Store? The answer is yes, just do not purchase anything other than 100% Pure Silicone (color does not matter) and I strongly recommend brand loyalty as there are good reasons behind GE and Dow Corning patents. To be safe, if you are unsure of the silicone you are buying, do not try and save a few bucks at the local hardware store when your local Pet Store or Aquarium Store have the correct product for maybe a few dollars more (unless an exploding aquarium in the middle of the night is your idea of excitement).
If you can not find quality Aquarium Sealant (either Dow Corning or GE, or one of their repackaged brands such as DAP or All Glass Aquarium; which hold patents for a good reason), please click on the picture to the left for an online source.

POND VEGGIE (PLANT/BOG FILTERS); The four basic types of veggie filters and how to install them.

Updated 6/10/10


Umbrella Plant

Bog Plant or “Veggie Filters” are very popular with many pond keepers. I have been using this method for pond filtration for a few decades (long before the term veggie filter became popular). Veggie (plant) filters are excellent for removal of many nutrients that cause green or cloudy water (including nitrates, phosphates, etc.)
There are two basic methods (that I am aware of), the more popular method nowadays is a separate pond filter. This is not my preferred method, however both work very well (I will discuss each latter). Any plant with a good root structure that grows fast and has the majority of their leaves above water (basically a bog plant) is a good candidate to start with. I recommend water iris for their strong root structure, fast growth, great nutrient absorption, and a great place for baby fish (fry) to hide feed and grow.

I prefer my Bog-plant filters within the pond as these look more attractive in my opinion and give the fish fry a place to hide (except in the case of the waterfall or cascade plant filter).
The area of the veggie filter should be relatively shallow as well to force water movement over and through the roots
There are many other excellent plants as well such as Sweet Flag, Parrots feather, Bluebells, Umbrella palm, Papyrus, & bull rush. Make sure these types of plants (plants with roots in water and leaves above) are planted in an area of good, but not strong water movement. This ensures that they will do their job as plant filters.

Please note that having a few Water Iris, Umbrella Palms, etc in a pond does NOT constitute a Veggie (Plant) Filter. For these plants to work as a filter you must have a small current of water around the roots or tubers, as well the use of substrate such as Volcanic Rock further increases filtration by allowing for the propagation of nitrifying and de-nitrifying bacteria as well as some mechanical filtration as well (trapping of debris). The mechanical aspect can be further increased by the addition of coarse polyester filter pads in the water column entering the Veggie Filter.
Often person will consider many floating Lilies a Veggie Filter, however they do not constitute a Veggie Filter, as although they certainly help block sunlight and remove some nutrients form the water column (which in turn can help control green algae), Lilies or other floating plants due not have the substrate roots, effectively remove nutrients and work with the substrate around them the way a true Veggie Filter can that uses Bog Plants.

A FEW SUGGESTED VEGGIE FILTER/BOG PLANTS (& Online Sources to purchase them)

Water Iris
Water Iris
This website here in Oregon ships beautiful Water Iris that can be used in your Water Garden, Pond; in particular your Veggie/Plant Filter.

The Water Iris is my personal Favorite, and grows in most climates from mild winters to more harsh winters (check individual specimen). Several varieties of Iris thrive in water gardens. I enjoy their graceful upright leaves and elegant blossoms. Iris flowers are several inches across and appear in early to late spring (depending upon climate) and dead blossoms should be clipped so as keep plants looking good and healthy. The plants will spread and form large tubers if given enough room. The yellow water Iris requires full sun, but the other varieties will bloom if they receive a minimum of three hours of direct sunlight, although they may become spindly.

Umbrella Plant
This is tropical bog plant, but can be grown in some cooler climates (such as high deserts of California if a freeze is not too hard).
Stems are 3-4 feet tall with the classic “umbrella (similar to the Dwarf Papyrus except the foliage is broader and the stems are taller). Best grown in full sun, partial shade, or filtered light. Plant Umbrella Palms in wet soil or in water up to 6 inches deep. For cooler climates it can be over-wintered as a houseplant if kept wet and given enough light.
The Umbrella Palm can take over a pond if not contained, so either use pots or keeping them strictly in sectioned off Veggie Filter.

Arrowhead
Arrowhead
Purchase these at PondPlants.com (click on the picture)

Another popular bog plant for pond veggie/plant filters.
Arrow head pond plants grow 2-3 feet tall in full sun and have large leaves and small white cupped flowers. These are best planted in 2" inches of gravel/fine volcanic rock in your Veggie Filter, with no more than 6" inches of water over the base of the plant or in pots with good top soil covered with gravel. Best in full sun or in partial shade.


A FEW TIPS

I recommend starting your veggie filter plants in pots (I prefer ceramic or even the bio degradable type) as these will contain the plant roots in the beginning, yet allow growth of the roots out of the pots. I highly recommend using Volcanic Rock in the area around the pots to fill in the gaps and allow for additional filtration. The advantage of volcanic rock is that its porous structure allows formation of aerobic bacteria for nitrification and anaerobic bacteria for de-nitrification. This further enhances your veggie filters ability to keep a clear pond by removing the nutrients necessary for green water/algae. The volcanic rock is also an excellent growth substrate for the plant roots as your veggie filter grows.

If water movement is poor in the area of your Veggie Filter (plant roots), I would recommend a submersible pump placed near the veggie filter with its outflow aimed at the veggie filter. Make sure this current is not too strong, so angling the outflow if the current is causing too much disturbance of the roots, volcanic rock, etc. Another way to circulate water in the area of an in pond Veggie Filter is to add a fountain to your submersible pump so as to have a more gentle spray in the area of the plant/veggie filter. I generally use a pump with a flow around 500 -1000 gph around veggie filters in a pond of approximately 300- 1200 gallons (this may be increased or decreased depending on the pond size). The Via Aqua 2600 is an excellent pump for use here with a flow of 740 gph. Other suggestions include the Via Aqua 3300 or the Via Aqua DP-18000 Multi Duty Pond Pump for larger water flows or multiple applications.

Be patient with a veggie filter as unlike many other forms of pond filtration, a veggie filter takes a while to become effective (often a FULL growing season!). This is why it is a good idea to have additional filtration as well such as a Pressurized Pond Filter and a UV Sterilizer




VEGGIE FILTER METHODS & CONSTRUCTION:

Before the common methods are discussed, let me point out some basics in construction that is common to all.

First is sizing, generally I have found a Veggie filter that consists of not only the plants/roots, but also has 6-12 inches of volcanic rock in the root/substrate area (there are even more advanced designs than this too) will work vastly better than several potted or otherwise randomly placed bog plants (due to added filtration by bacteria and the trapping of debris for plants to also more easily utilize). Assuming this combination of plant roots and tubers I have found that a mature Veggie (plant/bog) Filter of about 10% in surface volume as compared to the surface volume of the pond works well.
I have found that surface area works fine as compared to other calculation methods (which work too), as it is often the surface area that determines gas exchange & sunlight exposure. I will admit that this method of calculation does not take into consideration fish numbers, but considering average depths of 2-4 feet and healthy stocking numbers this has rarely failed me in calculations.

Some sub-methods of these basic designs include pulling water through the Veggie Filter bottom or pushing it upwards using slotted PVC. This idea certainly has the advantage of increasing flow to the roots and aerobic bacteria for ammonia/nitrite removal, however the downside can sometimes adversely affect some plant roots/tubers and often does not allow for de-nitrifying anaerobic to propagate for important nitrate removal (which is important for green water control). For this reason I do not promote this method of construction.

For me a better advanced addition to these methods (listed below) is to add an egg crate (or similar) before water enters the Veggie filter to support a pre-filter of coarse filter media and sometimes micron filter media as well. For corner Veggie Filters (or others) the use of a spray bar where the pump irrigates the water over this pre-filter works well too.




[1] Corner;
Place your plants in a shallow corner of the pond with ½” -2” rock under the plants to allow the roots to better establish themselves, do not use sand or soil. The water depth is best if the roots are barely covered by water. Add a slow to moderate (200- 600 gph) separate water supply (a diversion from your main water pump or a separate pump) to these plants make sure the water passes through the plant roots, not just over them.
An air pump such as a ReSun 9603 or Million Air 600 can also be used and placed in the middle to draw water in via the rising air column.

[2] Constriction;
Similar to above, place your plants in a shallow corner of the pond with ½” -2” rock under the plants to allow the roots to better establish themselves, do not use sand or soil. The water depth is best if the roots are barely covered by water. In this case, allow the water to move from one pond to the other thru this constriction area in a manner that maximizes root exposure to the water flow (again, not high a flow)

[3] Waterfall;
In this method the plants are in the waterfall or cascade area of the pond. Again place your plants in a shallow corner of the pond with ½” -2” rock under the plants to allow the roots to better establish themselves, do not use sand or soil. The water depth is best if the roots are barely covered by water. This method can be combined with other methods. The downside to this method if used by itself is it does not give the fry a place to hide and often water flows and water depths are harder to control for maximum efficiency, however this method still works especially when used in combination.



[4] Separate Veggie Filter;
This is a more popular method lately, although my least favorite.
In this method you would use a container such as a tub or small pool and pump water into these “Plant Filers” then water flows back into the main pond. I have seen nicely set up separate veggie filters where they are actually constructed into the ground or into a terrace, these do look better than the tub methods (these are more similar to the waterfall method). My problem with this method is similar to the waterfall method in that flow around the roots and water level (just above the roots) is hard to control to maximize benefits of the plant root structure. You also loose the benefit of a place for fry or breeding adults to hide as in the first methods.


CONCLUSION;
A Veggie or Plant Filter is an excellent compliment or even stand alone pond filter depending on the volume and filter (root) area and exposure of the plant filter.
A good compliment in a small pond would be a Hydro Pond Filter . The Hydro Pond IV can be connected to your Pump as a pre filter (these are rated up to a 1500 gallon pond), then a UV Sterilizer in line (best if used at slower flow rate) would further compliment this system (& is highly recommended). Another complimentary filter for a smaller pond (under 500 gallons) would be the Via Aqua BF2000 pump filter combination.
For larger ponds complimentary filters could include DIY water fall filters utilizing volcanic rock, plastic mesh, and poly pads or multiples of filters such as Pressurized filters (which are among the most efficient in design in my experience).
A good pump for medium to larger ponds that can run multiple features (including your Veggie/Bog Filter) would be the Via Aqua 18000 Multi-Duty, which is a hard pump to beat when one considers performance, reliability, design, and price.

As for the pump, I recommend the Via Aqua Pumps as they are a good combination of state of the art impellers coupled with proven electromagnet motors and value.

FOR MY FULL POND ARTICLE, please visit this link:
“A CLEAR POND, PROPER POND FILTRATION, CLEANING & MORE (even pond scarecrows for predatory birds)”