FRESHWATER VELVET - Piscinoodinium pillulare (also known as oodinium)
Also Information about Costia (Ichtyobodo)



Velvet (Piscinoodinium pillulare) is a flagellate parasite with chloroplasts, while ich is a ciliate, both have similar life cycles, but unlike ich, velvet can use its chloroplasts during dormancy to survive (which is where light can help), but in a full blown infestation, the parasites get their nutrients from the host and are NOT dependent on their chloroplasts.

This is an area of some controversy as some old school methods claim light and salt (sodium chloride) will treat and cure velvet, this has been proven false along with the assumption that this is a parasitic algae (due to having chloroplasts), this is not true. This is a flagellate protozoan.
This parasite is more resistant to higher salt levels than ich (Ichthyophthirius multifilis) and uses the chloroplast to produce nutrients (via chlorophyll and light) when a host is not available or to supplement nutrients derived from the host. It should also be noted that Marine Oodinium parasites do NOT have chloroplasts


What Are These Parasites?

Piscinoodinium pillulare are flagellate protozoa, single-celled organisms that move around by thrashing their whip like flagella. There are many species of flagellates that are part of the normal intestinal fauna of fishes, and many more kinds of free-living flagellates make a living in the mucus of fish gills and skin, without attaching themselves or causing trouble, but even some ordinarily harmless ones can become pathogenic in stressed hosts. Piscinoodinium pillulare is not harmless; it puts down a root like extension and can burrow into the skin or gill tissues. Giardia lamblia is a similar flagellate protozoa in humans that can cause severe acute diarrhea which may lead to a chronic diarrhea and nutritional disorders.

Identification;



Look for fish that scratch or ‘flash’ their bellies in attempts to scrape their gills against stones or gravel.
Rapid respiration or fish that hide or sink to the bottom and clamp their fins, in classic symptoms of malaise. Velvet moves fast, faster than Ich. If you're unwary, you may not realize the fish is being attacked by Velvet until it begins to lose its glossy shine and seems to have patches of yellowish to golden-brown or rusty-colored varnish (which is where the term ‘Velvet’ came from). If you turn out all aquarium and room lights and point a flashlight at the fish, this will make Velvet more visible.

Velvet can also settle out in the gills, where it will send down a root like extension into the gill lamella and dissolves cells then absorbs their contents. This causes extreme gill itch and swelling. In really serious infections, the gill cover may also become swollen. Fish can be killed by Velvet in a few days, either directly from suffocation in the Gills or from secondary bacterial infections.

Treatment:

Copper Sulfate is one of the more effective treatments, as it kills both dormant (destrying the chloroplasts) and kills the free swimming stage as well.
Methylene Blue (this should be used as a medicated bath, buffered with other ingredients, or used in a hospital tank, not as a direct treatment in a display tank) is also very effective and has the added bonus of being a hemoglobin transfer agent for the blood just when the fish need it most.

Acriflavin, and to a slightly lesser extent, malachite green and formalin are also useful. Acriflavin can be used with Copper Sulfate to increase effectiveness without increased stress to the fish

This is why the Medicated Wonder Shells are one of the best treatments for FW velvet.
These medicated blocks contained buffered Copper, Acriflavin and Methylene Blue, three of the better treatments for this infestation along with malachite green. These blocks also add electrolytes and calcium, both essential to good healing.

Another possible treatment choice is Quick Cure, although I have not found this quite as effective for true FW Velvet as it is for Ich.

30 minute, twice daily medicated baths using Methylene Blue and possibly one teaspoon of sodium chloride (salt) per gallon are also very helpful for the treatment of Velvet (and related flagellate parasites as well).
For further information about the use of Methylene Blue, please see this article about chemical treatments: “Aquarium Medications; Chemical Treatments including Methylene Blue”

Back to lighting, this may help with low infestations just like salt does with ich in low infestations, but in a full blown infestation, just like salt it is overrated.
I have witnessed this first hand in my Aquarium maintenance business, even with lights off!

COSTIA

Costia is a single cell microscopic parasite that attacks the skin of fish. It is a flagellate similar to velvet, however without the chloroplasts. It destroys the skin, in mild cases the skin appears cloudy (again similar to Velvet), in severe cases the skin is open and bleeding. It usually attacks fish in a poor state of health or living in poor water conditions or in overcrowded conditions. Secondary bacterial and/or fungal infections can occur at the open sore area. Costia can only survive on fish. Costia usually inhabits the gill and skin and once attached to the host it destroys tissue at that site. Which is why when found in the gill, Costia is so devastating, when present in great numbers Costia will destroy gill tissue.
In very small numbers Costia presents little problem (symptoms for minor infections include sloughed off scales),
however in poor water conditions Costia can kill rapidly.
Costia does do well in temperatures greater than 86 degrees F.

Second picture is of mild Costia infestation with missing scales

Costia is often (and mistakenly blamed on scratching, flashing and similar in fish, however although fish with a Costia infestation may flash/scratch this is not a very clear sign of a Costia infestation and is more likely early symptoms of velvet, ich or simply stress from poor water conditions similar to shimmies (often caused by improper mineral/electrolyte levels).
Luckily, if what one thinks is a Costia infestation is actually Velvet, treatment is similar as above for Velvet (although I have found formalin/malachite green based formulas more effective for Costia and Acriflavin less effective for Costia).

For true Costia infestations, clean water with good parameters (ammonia, nitrites, nitrates, GH, KH) are a MUST. These include the medicated baths, Copper Sulfate, Quick Cure, and Medicated Wonder Shells

For information about aquarium treatments and medications:
AQUARIUM MEDICATIONS, treatments, how they work, and which ones to use and not to use.

Aquarium Ich
For information about Aquarium Ich; Ichthyophthirius multifilis and Cryptocaryon irritans treatment, identification, and life cycle, please visit this site




For information about Saltwater Oodinium (velvet): MARINE OODINIUM (Amyloodinium Ocellatum)

References:
The Skeptical Aquarist-Flagellates

http://www.reefs.org/

What is Usnea?

Scientific name: Usnea barbata
Usnea is a lichen of the family Parmeliaceae that grows in damp temperate woodlands and contains usnic acid. I have found it effective for bacterial (some gram negative and most gram positive), fungal and even parasites such ich.
The other active ingredient (besides usnic acid) is mucilage.




A natural antibiotic it has also proven effective against gram positive bacteria, such Mycobacterium tuberculosis (making Usnea a great alternative to Isoniazid). Scientists believe that usnic acid works by disrupting cellular metabolism, either by preventing the formation of ATP which is the cells' energy source or by the stopping the action of oxidative phosphorylization. Usnea may also be a better choice than the drug metronidazole (as per human studies) for parasites and anaerobic bacterial treatments in aquariums.
Usnea contains potent antibiotic and antifungal agents that are broad spectrum and effective against all gram-positive and tuberculosis bacterium.

It is also noteworthy that Usnea is edible, with no known toxic side effects from ingestion in animal and human studies and as well is an excellent source of Vitamin C as well.

More information about Usnea;

Test tube studies have suggested an anti-cancer and an anti-viral activity for usnic acid. This may also make Usnea useful for the hard to treat aquatic viral disease; Lymphocystis (which is usually not fatal in otherwise healthy fish). The human studies can also be transferred to fish for tumors. I personally have not tested this enough as of writing this article, but based on human studies and the few tests I have done, usnic acid shows promise here.

Here are preliminary results based on my tests and tests on humans or veterinary application that can be extrapolated to fish:

*Topical treatment. This is where there is a lot of evidence is for usefulness. This has been shown in human and my own treatments to be very useful for wounds (many Native Americans used Usnea as a compress for battle wounds to prevent infection and gangrene)

*Gill infections due to the Mucilage (gluey substance produced by most plants and some microorganisms) contained in the Usnea which has been shown to have healing properties in areas of respiration.

*Digestive problems (which is an area where much human research also has shown significant effectiveness). Usnea can be a replacement for Neomycin or Metronidazole for use in digestive diseases, possible swim bladder infections and even possibly Dropsy (although there is limited evidence of usefulness for Dropsy as of yet).

*Tumors and cancers in fish, especially Carp Pox which is very coomon in Koi and Goldfish and often appears as tumor like growths, usually "whitish" although sometimes the same color as surrounding scales (this though is more likely a tumor)
-VERY Preliminary reults so far.

*Fish Tuberculosis

*Intestinal Problems, Usnea (usnic acid) has similar properties to Metronidazole here.


Symptoms of Lymphocystis:

* Whitish patches or irregular growths on the fish most commonly on the tail and fins.

* These eventually become quite large and give rise to the name Cauliflower Disease.
This remedy is still in the testing phase, but early results are promising. The Usnea Lichen is proving to be the most effective natural remedy early in my testing this lichen is boiled like a tea then added to the aquarium. The only dangers that have been established (in human studies) are in rare cases liver damage, which would make this a poor choice for dropsy.


Application:

I boil one small sprig in 6 oz. of water and add this to every 10-20 gallons of water every day until cure is effective +2 days

If interested in some Usnea for your own trials, you can purchase (.2 oz, enough for 200 gallons of treatment for $8.94 including shipping), please use this Google Button to purchase (it can also be purchased in the last drop down in the Pay Now menu here: SeaChem and other treatments):

There are two basic types of aquarium heater (and a sub type)
Also other heating elements for small tank/bowl use such as Bettas

Another term for the automatic heater is a Non-Preset Heaters, while the Thermostatic heater is also referred to as a Preset Heater.

As for heating requirements, I recommend 25 watts for every 10 degrees of ambient temperature per 10 gallons you need to raise your aquarium temperature. EX: If your home is 68 degrees and you have a 40 gallon aquarium, to reach a temperature of 78 degrees you would need a 100 watt heater. Often when heater problems occur it is due to the heater being of the improper wattage to meet heating requirements of an aquarium in the location it occupies. Too high a wattage can result in rapid temperature rises that can result in cooked fish if you make adjustment mistakes.
Also, if your room is warm (such as in summer months) you may end up with aquarium temperatures higher than your settings (example: a room that is 85 will keep an aquarium at 85 even if your heater is set at 78 F).

It is important of all heaters, regardless of type to maintain good circulation around the heater for the best results for temperature control and accuracy. I have used (& even designed my own) heater modules for in-line heater applications and I will be the first to admit these do not properly dissipate the heat, especially with titanium heaters.
Even though I really like the durability of Titanium Heaters, these types of submersible aquarium heater are best used inside the main display aquarium where the heat will dissipate more rapidly than in a sump or similar enclosed space. I have witnessed Titanium Heaters (of different brands) over heat and burn out when used in small sumps. I recommend using a glass submersible heater in sumps or similar as glass submersible heaters due not seem to be as sensitive to this problem.

Set Up Suggestions
When ANY heater is to be initially used, you should place the heater in the aquarium for 20-30 minutes prior to plugging it in so as to allow the temperatures to equalize internally. With low end Automatic Hang on the Back heaters make sure that the water is up to the water line, if too high or low this can cause heater failure or malfunction.
With pre-set submersible you need to make sure that the heater is submersed at least to the minimum water line.
Since Automatic Heaters generally do not have temperature pre sets, all inputs of temperature control on the dial should be made in increments of not more than ¼ turn, with 1/8 turn being better.
With Pre-sets and digital heater controls, I recommend to not change temperature more than 4-5 degrees F per day if fish are present (this doe not matter if there are no fish or other “creatures” present). Also make note that temperature pre-sets are just a guide and that it is quite common to set a heater at 75 F and have the actual temperature be plus or minus 3 degrees F.

PRESET HEATERS:


The Thermostatic or Preset Heater has a built in thermostat (or a remote sensor as is common in many titanium aquarium heaters). These heaters may use a digital thermostat, usually monitoring the impedance of a thermistor (a resistor used to measure temperature changes in the aquarium, relying on the change in its resistance with changing temperatures), or the potential across a thermocouple (a temperature sensor used to measure electric potential difference).
There are many models of aquarium heaters available today that come preset or with a temperature gauge on the side of the heater or on the control knob to help the aquarist set the temperature. The aquarist should allow the heater to adjust to water temperature for 30 minutes before plugging in this type of heater to allow the thermostat to adjust. Use these settings on the dial as a guide to make fine adjustments, as they should not be depended upon for total accuracy... Though some manufacturers make other claims, these gauges are at best accurate within two or three degrees Fahrenheit (one to one and a half degrees Celsius), and generally get less accurate over the life of the heater. An aquarist should always check their heater for accuracy and not assume that because it is set at 78 F, it will stay at 78 F.

It is not un-common for even the best of these heaters to be off from their “pre-settings” by a few degrees, so for instance if your pre-setting takes a setting of 76 F to maintain 78 F (& 78 is what you desire), you should use the setting of 76 F.

I also recommend turning off all heaters when water is to be changed that would exposed any part of the heater sensors or heating elements (which is usually most water changes). I recommend waiting at about 10 – 15 minutes for water and heater temperatures to equalize before re-starting a heater after a water change

Titanium/ Stainless Steel/ Remote Sensor Heaters

A subtype of the Preset heaters is the Titanium and Remote Sensor Heaters such as the Via Aqua Titanium heater The advantage to these heaters is twofold; one is that they tend to be even more accurate by having the sensor far from the heating element, and two; the Titanium (and also Stainless Steel) heaters are much more durable and difficult to break especially with large fish such as Oscars. These heaters also resist breakage due to aquarist mistakes such as leaving them on during water changes or dropping rocks on them (although Titanium heaters still can be damaged by leaving them on during a water change).

I think Titanium Heaters are your best choice for very large aquariums and for aquariums with large and destructive fish such as Arowanas, Oscars or even Turtle tanks (provided there is adequate water volume).
Titanium Heaters are NOT as good a choice for placing in confined spaces such as sumps, low water tanks (such as Viviariums) or filters such as the ReSun Internal Wet Dry Filter as Titanium heaters tend to easily overheat in confined spaces. In the case of a sump, the reasons for spending extra for a Titanium heater which are impact resistance and the remote sensor are lost in this small space where the remote sensor is of little advantage and no fish are present.

Please note that my experience with the Marineland Stealth Heaters indicates that they should also not be used in confined spaces or low water volume applications. I have also noticed (in part from feedback from others in the professional aquarium maintenance business) that the Marineland Stealth heater is not as accurate or as durable as the higher end Via Aqua Titanium Heater (or similar ReSun) or the very high end Pro-Heat II Titanium IC Heaters.


AUTOMATIC OR NON-PRESET HEATERS (HOB Heaters)


The Non-Preset or Automatic heater such as the basic Hawkeye or Radiant Heater has a very remedial thermostat; or better they have metal contacts that are tightened by turning the dial (metal contacts installed on bi-metal lead, which are brought together with an adjusting screw). When the heater is "turned up" or tightened, it turns on for longer periods of time. These heaters need adjustments between summer and winter. Examples of this heater are the Radiant by Hagen, or even the old Metaframe heaters. Sometimes these heater are all some aquarists can fit or afford on their tank (although Thermostatic heaters have come down in price a lot), but I have seen many an aquarist cook their fish with these, as subtle changes in the dial often over correct and a sudden ambient warm spell is often not corrected for.
With these heaters it is imperative that the water level is kept up to the proper level as marked on the heater or they may crack, it is also important to check these for seasonal variations (Summer/Winter), as these heater adjust poorly for these. These heaters should not be used in a room or garage with wide temperature swings as they will not generally adjust properly. Adjustments with these heaters should be made at no more than 1/8 turn at a time then wait for about two hours before the next adjustment.

As with other heaters it is a good idea to place the heater in the tank and wait for 30 minutes before plugging in (although this is less important with these automatic heaters).
Adjustments should be made very gradually and it is easier to adjust these heaters if you start out at our near the desired temperature, otherwise you may be in for a rollercoaster of adjustments.

Other Aquatic Heating Devices

As for heating betta in a small tank or bowl, this can be difficult with even the smallest aquarium eaters as they tend to be less accurate in very small volumes of water.
I have used (also for my clients) infrared reptile lamps or infrared heating elements (these are generally more pricy and not worth the extra money for a fish, unlike a reptile) placed in desk lamp s over the tanks with the distance set according to the temperature desired. The distance will need to vary based on ambient room temperature. The nice part about using these reptile infrared lights is that they do not interfere with the day/night cycle of the fish the way a white light or even a blue light will.
These are actually quite accurate when used correctly and more importantly they do not upset the day/night cycle needed by fish.



SUMMARY:


When choosing the right heater you need to factor your budget, tank size, fish size potential, ambient room temperature variation, and temperature sensitivity.
For example: a 10 gallon (35 liter) aquarium with platties and guppies would probably be fine with an inexpensive Automatic Heater, the same for a small Betta Tank. But if this tank was in say a shed where temperatures vary greatly, even this example would be better of with a Preset heater (for Bettas I have also used infrared reptile lamps in desk lamps to maintain temperature successfully while still allowing day/night cycles).
Another example would be fish such as Oscars; with Oscars I would recommend the stainless steel or Titanium heaters as these fish can get rambunctious.
A third example would be marine fish; marine fish generally are not accustomed to much if any temperature swings so a Preset (thermostatic) heater would also be in line here.
Finally for any larger aquarium (40 gallon +), a Preset heater just makes more sense in my opinion.


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The Lateral Line in Fish as well as Lateral Line Disease or Head and Lateral Line Erosion (HLLE)


The lateral line is a sense organ that consists of a row of scales that most fish have along their sides, extending from their head to tail. Under these scales are a system of fluid-filled canals and specialized cells which transmit vibrations to the brain of the fish. The lateral line helps fish to detect movement and vibration in the surrounding water including predators and prey. The lateral line or similar organs in fish such as blind cavefish (which has rows of neuromasts on their heads) are used precisely to locate food without the use of sight. Killifish can sense ripples caused by insects struggling on the surface of the water. Scientific experiments with Pollack Fish have shown that the lateral line is also used for schooling behavior.

Identification:

Lateral lines are usually visible as faint lines running lengthwise down each side, from the area around the gill covers to the area near the base of the tail. Sometimes parts of the lateral line are modified into electro-receptors (biological ability to receive and make use of electrical impulses), which are organs used to detect electrical impulses.

History:

A Scientist in the 1960s named Sven Dijkgraaf argued convincingly that fish must use their lateral lines to detect water motion. This motion can be generated by the fish, water currents, or by some external moving object. The lateral line seems to have the ability of detecting the subtle movements of biological sources (prey fish or predator fish, for example) located some distance away. Many scientists believe that fish such as sharks can use these organs to detect magnetic fields as well.

How the Lateral Line Works:

There are receptors in the line, called neuromasts, each consist of a group of hair cells, these cell hairs are surrounded by a protruding cupula (an organ that gives an animal a sense of balance). Neuromasts may occur singly, in small groups called pit organs, or in rows within grooves or canals, when they are referred to as the lateral line system. The lateral line system runs along the sides of the body onto the head, where it divides into three branches, two to the snout and one to the lower jaw. These neuromasts are usually at the bottom of a pit or groove in the fish, which is large enough to be visible. Skates, rays and sharks usually have lateral-line canals, in which the neuromasts are not directly exposed to the environment, but communicate with it via canal pores. The hair cells in the lateral line are similar to the hair cells inside the others vertebrates inner ear (such as the cupula in humans where hair cells within the cupula sense rotational acceleration), indicating that the lateral line and the inner ear share a common origin. Some active fish that are constantly swimming tend to have more neuromasts in canals than on the surface, and the lateral line will be further away from pectoral fins, to reduce the noise generated by fin motion.
The lateral line system, found in many fishes, is sensitive to differences in water pressure. These differences are thought to be due to changes in depth or to the current like waves caused by approaching objects. When pressure waves cause the gelatinous caps of the neuromasts to move, bending the enclosed hairs, the frequency of the nerve impulses is either increased or decreased, depending on the direction of bending. A swimming fish sets up a pressure wave in the water that is detectable by the lateral line systems of other fishes. It also sets up a bow wave in front of itself, the pressure of which is higher than that of the wave flow along its sides. These near-field differences are registered by its own lateral line system. As the fish approaches an object, such as a rock or the glass wall of an aquarium, the pressure waves around its body are distorted, and these changes are quickly detected by the lateral line system, enabling the fish to turn or to take other actions. Because sound waves are waves of pressure, the lateral line system is also able to detect very low-frequency sounds of about 100 Hz or less.

An adaptation of the pressure-sensitive systems is seen in the modified groups of neuromasts called the Ampullae of Lorenzini (special sensing organs, forming a network of jelly-filled canals), which are found in sharks, rays and a few bony fishes. The Ampullae of Lorenzini are able to detect electrical charges, or fields, in the water. Most animals, including humans, emit a DC (Direct Current) field when in seawater. This is thought to be caused by electrical potential differences between body fluids and seawater and between different parts of the body. An AC field is also set up by muscular contractions. A wound, even a scratch, can alter these electrical fields.

Diseases of the Lateral Line:


Often the lateral line in fish, marine in particular will get infections or degenerate from water conditions. Many believe Marine Head and Lateral Line Erosion is related to Hole in the Head (HITH).
The usual progression in marine fish of MHLLE (Marine Head and Lateral Line Erosion) is usually the development of small pits around the eye and on the head and adjacent area. As the ailment progresses, the holes grow larger, eventually connecting to become larger lesions, eventually extending back along the fish's lateral line. The fins and gill covering will also often erode in more advanced cases, although MHLLE is seldom fatal. Yellow Tangs for an unknown reason progress differently; they tend to lose their vibrancy and lighten in overall color, followed fin erosion, usually beginning with the soft tissue between the dorsal fin's rays.
In general Marine Angels and Tangs (Surgeonfish) seem to be the most susceptible.

Theorized Causes

Vitamin, immune system
Vitamin and mineral deficiencies such as Vitamin C and possibly Vitamin B complex are one very likely cause of degeneration from my experience. Proper feeding of foods high in these vitamins such as Spirulina Algae will help in this case.
These deficiencies along with poor water quality (which often results in poor Redox) show the most evidence for being the major cause of this affliction.

Many have attributed high nitrates due to poor water quality as a possible cause, however although low nitrates are certainly important for long term health, I believe high nitrates play a minor role in how poor water affects HLLE in fish. I believe from my own tests (as well as research) that the lack of minerals and vitamin in low quality water along with a poor Redox Potential are the main culprits. I have witnessed Yellow Tangs turn around with the addition of trace elements in client’s tanks that previously never supplemented them.
As stated earlier the use of products such as Spirulina Algae , high quality additives such as Kent Marine Zoe, adding trace elements/ complete buffers as well a simple and basic water changes using quality salts aids profoundly in maintaining proper mineral/vitamin levels in marine fish, especially since marine fish constantly drink the water around them which makes their body chemistry very much like that of the water around them.

Another aspect of water quality, immune system health is the The Aquarium Redox Potential, without going into a long explanation, simply put a correct Redox potential acts as an anti-oxidant clearing away free radicals much the way many vitamins such as A, C and others do. Many aquarists are unfortunately unaware of this aspect of the aquarium keeping even though many human studies have shown direct correlation to correct Redox and lowering of free radicals.
PLEASE reference this article for more on this subject:
“The Aquarium Redox Potential”,


Stray Electrical Current
Another theory is that an un-grounded aquarium can cause electrical fields that both interfere and degenerate the lateral line in fish. You can test this by using a pocket multi-meter on AC volts with a probe in the wall ground and a probe in the water. HOWEVER, newer evidence does not seem to support this theory which quite bluntly from my experience makes sense as I have witnessed many broken or leaking electrical devices over years that I can actually feel the “stray” electrical current by hold my hand just above the water or if I have an open cut, YET the fish do not seem to be affected UNTIL one completes the circuit (such as a Pacu I witnessed that “bit” into a loose set of wires that a client had left in hanging into the tank, all was fine until the fish “completed” the circuit. My point is that there is NO completed circuit until you complete it with a ground (which you do when touching the water while standing on the ground.
For further information, please see this article: Stray Voltages Explained

Other Theories
Other HLLE theories include the use of activated carbon, however in admittedly non-controlled studies I have seen no difference in occurrence or cure with the use of carbon, however it is possible that many are not keeping up with trace elements, and have a poor Redox and then the addition of carbon might remove what little anti-oxidants there are in an aquarium, but I do not think one can safely state that the use of carbon will lead to HLLE.
Exposure to Copper is another theory, however once again since I used to use copper extensively many years back I never observed any such correlation.
Viruses, bacteria and parasites have also been blamed and once again I have not seen enough supporting evidence to support this theory as well.

Finally two more theories that do make sense (although not scientifically proven) are lack of sunlight or correct Lighting. Proper lighting is another (or lack thereof) is another parameter for a healthy lateral line in fish. Full spectrum lighting such as a combination 6,400 K or 20,000 K bulb and Actinic (UVA) bulb will help with this. The thought is that full spectrum lighting aids in the assimilation of certain vitamins, much as in humans and Vitamin D.
Chronically stressed fish is one more theory that seems quite plausible from mine and others non scientific experience.

References:
The Krib- Lateral Line Disease
Hypothesis of Head and Lateral Line Erosion in Fish, Part 1
Hypothesis of Head and Lateral Line Erosion in Fish, Part 2
Hypothesis of Head and Lateral Line Erosion in Fish, Part 3


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What should I know about tap water for my aquarium?

There US standards for tap water quality (and I am sure other nations such as the UK have their own regulations too), but that does not mean that these allowed levels are safe for fish (or humans for that matter)

CHLORINE AND CHLORAMINES:

To start with most city tap water has chlorine (Cl or as in chlorine bleach, sodium hypochlorite NaClO), which is an oxidizer (A chemical substance that gains electrons in a redox chemical reaction), but this can kill fish by burning their gills and poisoning their blood.
Some municipalities use chloramines because they are more stable than chlorine. Chloramines (NH2Cl) are a chemical compound of chlorine and ammonia and cannot be boiled our or allowed to sit for a few days to remove them before adding this water to an aquarium. For more in depth information, please read this outside article about Chloramines: "Chlorine and the Reef Aquarium".

You will need to remove chloramines chemically before adding tap water that contains this to your aquarium. Standard de-chlorinators such as “Start Right Water Conditioner” will remove the chlorine, but leave the ammonia (NH4) for either your bio filtration or Zeolite (freshwater only) to remove. These basic de-chlorinating products are simple Reducers (sodium thiosulfate) and are quite safe, even overdosed contrary to some opinions floating around.
Products such as Amquel or “Prime- (Removes ammonia, chlorine, chloramines, ammonia)” will remove the chlorine and neutralize the ammonia (and more). Prime is made from Hydrosulfite salts which are basically non toxic reducing agents made up of bisulfites and hydrosulfites, aqueous solution, buffered at pH 8. As mentioned earlier, reducing agents are basically non toxic at reasonable doses to fish and aquatic animals. Please see my article “Aquarium Redox Potential; How it relates to proper aquatic health”.

The chart to the left shows some common chlorine/chloramines reducing agents.
You will note that metabisulfites and bisulfites are efficient reducers, however it should be noted that some studies have shown these to lower dissolved oxygen levels. I have never had a problem with this due to the fact I always employ good circulation when ammonia, chloramines, or chlorine are a problem (actually good circulation should usually always be employed). You will also not the Vitamin C (ascorbic acid is also an effective reducer, which also goes along with many of my points for a Reducing Redox).

For much more information about water conditioners that will remove Chlorine and/or Chloramines, please read this article: “Aquarium (& Pond) Water Conditioners”.

INORGANIC CHEMICALS; Nitrites, Nitrates, Copper, Phosphates, and Fluoride:

Nitrites are allowed up to 1 ppm, yet at this level there can be some damage to fish gills. “Methylene Blue (for nitrite and ammonia poisoning)” can be used for treatment of nitrite poisoning, but it is best to avoid this. A good bio filter will generally remove trace amounts of this from tap water, as will products such as Prime.

Nitrates are allowed up to 10 ppm, yet at levels above 10- 30 (depending on studies) in human studies infants under 6 months can become ill and suffer symptoms such as Blue Baby Syndrome. See these links:
http://www.epa.gov/teach/chem_summ/Nitrates_summary.pdf
http://www.thirteen.org/edonline/studentstake/water/schoolwater/nitrogen/nitrate.htm
Now this level has shown no ill effect in any fish studies I have seen, but levels above 20 ppm can harm some marine cephalopods. It makes since in many marine aquariums too use RO water to mix up your salt mix or top off for evaporation so as to not add to hard to remove nitrates in you marine aquarium.

Other allowed chemicals of note are Copper- 1.3 ppm, Phosphates (no standards) and Fluoride- 4.0 ppm. Copper at these levels is not generally a problem with fish or aquatic invertebrates, but if you are already treating with copper sulfate or if this is allowed to accumulate in a reef tank this is something an aquarist should be aware of. Copper levels above 5 ppm can start to become dangerous for some delicate invertebrates such as corals and levels above 25 ppm can be dangerous to fish. It also should be noted for copper, that in hot water in particular, copper can be also added to tap water via home copper plumbing.
As for Fluoride; I have not found conclusive studies on the harm of Fluoride to fish or other aquatic creatures, in fact trace amounts are necessary for coral growth in marine aquariums. So despite over stated worries about Fluoride in tap water used in aquariums, this in one I would not consider.
As for Phosphates; many municipalities use phosphates to reduce the levels of lead that have been found in drinking water. Phosphates create a protective film on the inside of the pipe, slowing the electrochemical processes that lead to corrosion. Unfortunately for aquarists this can lead to extra algae growth, especially of Blue Green Algae (Cyanobacteria). This can be a real problem in both freshwater and saltwater aquariums without easy solutions. I have used many phosphate sponges with mixed results, but I can say with certainty is that carbon will not remove phosphate, in fact some carbon may even add to your phosphate levels. Protein Skimmers in marine aquariums can remove some phosphates, but I have not recorded that much difference.
Water changes using RO water and then adding minor elements and electrolytes back in is another solution. In freshwater aquariums, “Wonder Shells – calcium and electrolyte replenisher” can help with this, but in saltwater the marine mixes have all the elements you need.

For a more in depth article about Aquarium Test Kits, please follow this link:
AQUARIUM TEST KITS; what they are used for and their importance.


SUMMARY:

Before you go and rush out and use nothing but bottled water, please note that most bottled water is not suitable for fish when used 100% (it can be mixed or reconstituted). Drinking Water in particular is generally RO water with some minerals added for “taste” (Spring Water is generally fine if it is true spring water). Not that there is anything wrong with RO or DI water, it is just they are devoid of VERY important electrolytes and trace elements needed for proper fish respiration and osmotic function, without which you may be worse off in terms of fish health than with slightly polluted tap water. So please use the information in this article to improve your water quality and make wise choices as to your water sources. Also please read this article about Aquarium electrolytes and more:
CALCIUM, KH, AND MAGNESIUM IN AQUARIUMS; How to maintain a Proper KH, why calcium and electrolytes are important.

Further Resources

For more information about U.S. government standards, please see this article:
“Drinking Water Contaminants”

For a map of the U.S. showing the distribution of soft and hard water see:
USGS: Common water measurements

What Does a Reverse Osmosis Filter System Do