THE DIFFERENCE BETWEEN PLASTER OF PARIS AND PRODUCTS SUCH AS WONDER SHELLS OR SEALAB

I have read in many places about the use of Plaster of Paris as a calcium source for both ponds and freshwater aquariums (I too have used this many years back when old timers in the hobby suggested its use for ponds to me), however with the exception of a calcium emergency (or possibly to absorb pollutants in a pond in bulk, which I have used Plaster of Paris for); Plaster of Paris is not the same as products such as Wonder Shells or Sealab blocks. My own years of use have shown me the vast difference in fish health and vitality.
In this article I will hopefully explain this a little more scientifically.


PLASTER OF PARIS:


Plaster of Paris is manufactured by heating gypsum at 120o - 160oC. When Plaster of Paris is mixed in water it dehydrates and form dense matrix of gypsum crystal.








Here is a list of ingredients of Plaster of Paris:

*CaSO4 , 1/2H2O: 97.97%
* SiO: 0.94%
* Al2O3: 0.69%
* Fe2O3: 0.28%
* MgO : 00.12%

What I see here is some Magnesium Oxide, Iron, Sulfur, Aluminum, Silica and mostly Calcium Sulfate.
Where is the Strontium, the Sodium, Potassium and more? These ratios are also NO WHERE near correct for proper assimilation.
This is not to say that products such as Wonder Shells or Kalkwasser are also spot on in these ratios, however they are much closer than this (or at least Wonder shells are). This also why Marine Buffer by Sea Chem is better for KH control as the proper ratios are applied in this product.

It is also noteworthy that Calcium Sulfate is not the best source for Calcium in a “living” aquarium environment; Calcium Hydroxide (Kalkwasser), Calcium Carbonate, or Calcium Gluconate (the calcium salt of gluconic acid, an oxidation product of glucose) are much better sources for calcium in an aquatic environment. In plant and animal studies, calcium chloride and calcium sulfate (found in Plaster of Paris), have been known to cause problems, however the problem is generally associated with the anions Cl- or S04 rather than calcium which is a necessary nutrient for plant and animal life and EVEN in high amounts is safe by itself or in the other forms I recommended earlier in the paragraph.
There is also a lot of mis-understanding in the aquarium community as to how VERY important bio-available calcium is (again Calcium Hydroxide, Calcium Carbonate, Calcium Gluconate; NOT Calcium Sulfate found in Plaster of Paris). Calcium is a very important mineral/electrolyte for so many body functions such as muscle contraction which is initiated by a sudden increase in calcium concentration in the muscle cells. Calcium is also important in times of stress, which is why a new fish added to aquarium that has poor bio available calcium is very likely to get sick and often the aquarist blames the opportunistic disease rather than realizing that the fish may be suffering form the lack of electrolytes such as calcium.

Another ingredient found in Plaster of Paris is Silica; this mineral can cause algae problems (especially brown) and is especially troublesome in marine aquariums.

Plaster of Paris is also a poor choice for GH or Calcium as Calcium needs to be in the proper ratios with other elements such as Magnesium to be utilized by aquatic life (such as osmotic function).


PROPER OCEAN CHEMICAL ANALYSIS:



By contrast here is the chemical composition of the ocean as a percentage:

Chloride- 55.03%
Sodium- 30.59%
Sulfate- 7.68%
Magnesium- 3.68%
Calcium- 1.18%
Potassium- 1.11%
Bicarbonate- 0.42%
Bromide- 0.19%
Borate- 0.08%
Strontium- 0.04%
Fluoride- 0.003%
Other- less than 0.001%

As you can see, calcium is actually less than magnesium, so even the Wonder Shells that I promote are out of balance here. The Calcium in Wonder Shells is used as a carrier and will raise your GH, at least the other proportions (with the obvious exceptions of Chloride and Sodium) are in basic proportion to this other than the Calcium.


For more about Calcium, Electrolytes in aquariums, please read this article:
CALCIUM, KH, AND MAGNESIUM IN AQUARIUMS; How to maintain a Proper GH & KH, why calcium and electrolytes are important.


RELATIONSHIP BETWEEN OCEAN WATER AND INTERNAL CHEMISTY OF ANIMALS:

I brought up ocean water chemical analysis to make a point that is the plasma and internal chemistry of all animals and fish is similar in composition to the ocean. This is why many electrolytes (elements) are important in the chemistry of aquarium environment (even fish food!)

Rene Quinton is a scientist who died in 1925.
"He postulated that from the mineral point of view, human and marine plasmas are environments of the same nature. In other words, there is physical and physiological identity between seawater and the internal environment of the organism. Not only do they exhibit very similar mineral compositions, but the particular form, organization and synergy of trace elements and mineral salts that make up the saline matrix of seawater closely resemble those of the internal environment constituents."

http://www.oceanplasma.org/

For more about proper Osmotic Function in fish, pleas see this article:
PROPER OSMOTIC FUNCTION

SUMMARY;


Basically my point is that all you add to your aquarium (freshwater or saltwater) should emulate this ocean ratio as close as possible. In saltwater fish are constantly drinking the water around them for proper hydration and osmotic function so they are very sensitive to their water chemistry. In freshwater the fish are absorbing the water around them for hydration and osmotic function so they are less sensitive to poor water chemistry, this said, that is why you can often get away with dumping Plaster of Paris in Aquariums or ponds. This in NO means you are providing the proper electrolytes your fish need. Using products such as Sea Chem Buffer or Wonder Shells are more likely to achieve a better balance here.
Besides, why would you want to throw a product in your aquarium manufactured by heating gypsum?

References:
http://web1.msue.msu.edu/imp/modf1/05209702.html
http://www.oceanplasma.org/
http://www.chemistry.wustl.edu/~courses/genchem/Tutorials/Vitamins/calcium.htm

NEON TETRA DISEASE (Identification, prevention and possible treatment of):


This term is often a catch all name for diseases of Neon Tetras specifically and many other fish as well.
The usual cause is by a Sporozoan (parasitic spore-forming protozoan which reproduce sexually and asexually in alternate generations by means of spores); Pleistophora hyphessobryconis, although there are other causes including many fungi that will imitate this Sporozoan infection.
The true Pleistophora hyphessobryconis infestation is very difficult to treat, and basically impossible to treat in the later stages of this infestation (which is when most aquarists first notice this disease). However, contrary to popular opinion on the web and elsewhere where many are just repeating what they hear elsewhere it is somewhat treatable in the early stages and VERY preventable from spreading.

Occasionally rare gram positive bacteria will also cause these symptoms (fading, loss of color, etc.) which require a different coarse of action.

ABOUT THIS INFECTION:

The disease cycle begins when parasitic spores enter the fish after the fish ingests infected food or organic debris, such as the bodies of dead fish, or live food (often Tubiflex Worms). After the spores enter the intestinal tract, the newly hatched embryos burrow through the intestinal wall and produce cysts within the muscle tissue. These muscles containing the cysts begin to die, resulting in a pale whitish tissue.
Initially the only symptom may be restlessness especially when lights are turned on and off. The infected fish often will stop schooling with others of their species. Soon the swimming becomes more erratic and the tell tale symptom of the white muscle tissue becomes apparent.


Other fish are susceptible to this infestation as well, this includes and is not limited too:
*Most Tetras
*Many Danios (including White Clouds)
*Angelfish

Symptoms in order of progression:

• Restlessness and sensitivity.
• The fish become more isolated
• The fish has difficulty swimming (at this point treatment will generally fail)
• The tell tale white/ pale tissue appears.
• As cysts develop and produce more spores, body may become lumpy or irregular.
• Often in advanced cases spine may become deformed or curved.

TREATMENT (and more importantly; stopping the spread of this disease):

A bath with Methylene Blue is the first step. To prepare this bath I use 1 teaspoon 2.303% solution per 5 gallons (double dose) in a bath of aquarium water from the tank the fish you wish to treat came from, I usually use about a ½ gallon of water, however you may use less. Measurement of the Methylene Blue does not need to be precise as this bath should be used for about 30 minutes (although do NOT overdose). Make sure you keep the water in a warm area, as in a cold room the water temperature can drop rapidly which would stress the fish. Do NOT pour this water back into your display aquarium when finished. This can be performed twice per day.
This bath is helpful for the both “True Neon Tetra Disease” and false neon tetra disease (FTT Disease).

In the tank you need to treat with Quick Cure , or ParaGuard-Parasite Treatment , or Medicated Wonder Shells (although Medicated Wonder Shells are better as a follow up treatment). Continue this treatment for 7-10 days.
If at all possible I strongly recommend at least temporarily attaching a UV Sterilizer (for more information about UV Sterilization, please read this article: ULTRAVIOLET STERILIZATION (How UV sterilization works) . This article explains the benefits and myths about aquarium and pond uv sterilization)
A medication containing Metronidazole or an additional treatment of Metronidazole can be very helpful as well (note: this is infestation is difficult to treat and takes a "medication cocktail" approach to defeat).

In the even more rare cases of FNT disease Erythromycin may be effective (I still recommend the medicated Methylene Blue bath).

If all these steps are followed my success rate in stopping the spread of this disease is nearly 100% and treating early stages at around 20% to 50%. If you cannot add the UV Sterilizer, the other steps will still help a lot, especially in stopping the spread.

SUMMARY:


I will note it is common to confuse true Neon Tetra Disease caused by the Sporozoan; Pleistophora hyphessobryconis with other diseases such as many fungi infections and even gram positive bacterium, I call these False Neon Tetra Disease or FNT Disease. These false infections often do not have the symptoms leading up to the white/ pale tissue and the discoloration is more faint and much less white and defined than True Neon Tetra Disease.

If all these steps are followed my success rate in stopping the spread of this disease is nearly 100% and treating early stages at around 20% to 50%. If you cannot add the UV Sterilizer, the other steps will still help a lot, especially in stopping the spread. However, it is important to follow as many as possible of these steps as Neon Tetra Disease does not spread in the same manner as other protozoan infections such as ich or velvet, making it difficult to treat. This is why this “treatment cocktail” is required.

AQUARIUM TEST KITS; what they are used for and their importance.

It is always best to have as many different test kits as you can afford (as they apply to either freshwater or saltwater

I prefer to purchase my test kits separately as most master test kits duplicate test I do not need (high range and low range ph) and leave out ones I need such as kH and GH, or possibly Phosphate, Calcium, or Redox.

Another important point to testing your aquarium is that it is always useful to know what your tap water parameters are for comparison to aquarium water, this way you can make educated decisions as to water changes or problems with parameters such as pH. It is noteworthy that tap water (including well water) needs to “gas out” before testing for pH as trapped CO2 will often give false readings of a lower pH until all the CO2 evacuates he water sample (I have seen more than .5 pH changes in gassing out). Please reference this article for more information about pH: “Calcium, pH, GH, KH and Electrolytes in Aquariums”

In marine aquariums it is also important to know what your pre-mixed water alkalinity, pH, and nitrates are as well as the water you use to top off for evaporation.

Here is a list of FRESHWATER Test Kits, followed by Saltwater Test kits (many tests overlap, so I do not give a full explanation always).


[1] Ammonia Test Kit ; Ammonia is very toxic even at low levels, should be kept at or near 0. Ammonia test kits cannot discern between highly toxic ammonia (NH4) and only slightly toxic ammonium (NH3). Products such as Prime , Ammolock, and Amquel will convert NH4 to NH3, so your toxic ammonia level will not test accurately after using one of these products. Ammonium (NH3) will convert to NH4 at higher pH levels, which why high ammonia levels as per test are much more toxic at higher pH.

[2] kH & GH Test Kit ; you will notice I placed this above a pH test Kit, this due to the fact that a poor kH will make keeping a stable pH nearly impossible. Also Calcium (as tested in GH) is more important to fish health than many aquarists give credit (see my article: CALCIUM, KH, AND MAGNESIUM IN AQUARIUMS; How to maintain a Proper KH, why calcium and electrolytes are important).
*You want to maintain a KH & GH of around 60/100 ppm respectively (around 2-3 dKH & dGH) for Discus, Rams, Cardinals, and other Amazon fish.
*A KH of 80-120 and a GH of 100- 250 for most tropical fish including Gouramis, Bettas, Angelfish, ECT.
*A KH of 100-160 and a GH of 150-300 for Goldfish, mollies, Platties, Guppies, ECT.
*A KH of 150+ and a GH of over 200 for Rift Lakes African Cichlids and Brackish fish such as Monos and Scats.
I also recommend th use of titration GH/KH test kits as these are far more accurate than test strips for hardness test whether general or carbonate. A Titration test kit uses a drop counting method to determine the degrees of 'German' hardness (one drop per degree) which can then be converted to ppm by multiplying by 17.9


[3] pH High Range OR Low Range Test Kit ; you should only need one or the other based on the type of aquarium you keep.
Does not stress over being exact about pH, as too of many aquarists go WAY overboard here! For example Discus generally do best around 6.5, however I know breeders of Discus using water with a pH well over 7.0

I recommend a High Range Test Kit for Goldfish and livebearers which should have a targeted pH of about 7.5-7.8. Rift Lake African cichlids should have a pH of over 8.0
I recommend a Low Range Test Kit for general community freshwater fish (6.8- 7.4) or Amazon River fish (under 6.8)

[4] Nitrate Test Kit ; this test is important to know when to change your water (along with KH), as well as how well your general long term tank health is going. Nitrates will also show you how well your plants are consuming nitrogenous nutrients, and if you are vacuuming the aquarium properly such as removing all the mulm. Some filters such as Under Gravel in particular, and Wet Dry and Canister filters can become nitrate factories if not taken care of properly.
For most freshwater fish a nitrate level under 40 ppm is correct or above 15 ppm for planted aquariums.

[4] Nitrite Test Kit; you will notice I put it lower on the list, not because it is not important, only that if budget is a concern or time for testing is a factor, this parameter mirrors ammonia often within hours or days. Nitrite should be at or near 0. This is of coarse still an important test, especially during cycling, however if money is an issue, I recommend that one waits for the ammonia to come down, then count about 3-5 days before adding fish.

[5] Iron Test Kit; Generally only necessary in planted aquariums.
Iron levels need to be carefully monitored in order to maintain lush, planted aquariums. It is recommended to test iron with a frequency that will maintain the suggested iron level of 0.25 to 0.5 mg/L.

[6] Phosphate Test Kit; generally only necessary in planted aquariums where large amounts of ‘ferts’ (fertilizer) are added or if you have uncontrollable algae growth. This test kit is often more important for ponds where rain water can wash debris with high phosphate content into the pond.
Another source of phosphates is tap water. 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 can lead to corrosion.
Poor quality fish foods can also be a source of phosphates in aquarium water. Try and purchase a dry fish food with as little as possible of processed ingredients. Aquatrol Spirulina 20 is probably one of the best basic flake foods available when it come to low phosphate content (and quality ingredients and nutrition as well)

Your aquarium (or pond) should have phosphate levels as close to 0 as possible.

[6] CO2 Test Kit; This test kit or similar (such as a CO2 drop checker) can be VERY useful for serious planted freshwater aquarium enthusiasts. I highly recommend using a KH test kit as well for the most accurate results. The Azoo pictured uses a titration method of counting drops after which you cross reference with your KH to determine the appropriate CO2 level for your planted aquarium; for example: 10-15 ppm CO2 (mg/L) at 5 dKH (90 ppm KH).
Please read this article for much more in depth information about planted freshwater aquariums:
“Planted Freshwater Aquariums”


[7] Redox Meter; generally this water parameter will take of itself provided you perform proper aquarium husbandry including, regular water changes with properly ionized water, you maintain a GH and KH level of at least 50 ppm (I find 80 ppm better). This said, this is a good parameter to check if you are having problems with Cyanobacteria (Blue Green Algae) or if you are having unexplained problems and every other test is correct (providing you do not have an unknown disease). I recommend every aquarist be at least familiar with the Redox Potential, here is an in depth article about aquarium Redox: “The Redox Potential in Aquariums (& Ponds) and how it relates to proper aquatic health” . You can use Methylene Blue according to standard dosage to your aquarium water (remove the water for this test), and it stays a brilliant blue, you probably have a positive Redox. If the color dissipates at all (even the slightest) you probably have a reducing number. This test in no way replaces the accuracy of Redox meter, but it is a simple way to get a handle on your aquariums Redox health.
Your aquarium Redox should be around -300 mV.



SALTWATER;
The list remains similar and I will bypass descriptions that are in common with freshwater test kits.

[1] Ammonia Test Kit; this should be 0 as in FW

[2] KH Test Kit; you do not need a GH Test Kit for saltwater. KH (or alkalinity as is called in marine aquariums) should be over 240 ppm (13 dKH)

[3] PH High Range Test Kit; your pH should be between 8.2 - 8.4


[4] Hydrometer; this instrument tests the specific gravity of aquarium water (in simple terms the amount of salts). There are two types; the floating glass hydrometers which are more fragile, but also more accurate or the simple needle hydrometer that you fill with water. It is important with both types of hydrometers to clean these with white vinegar (then rinse thoroughly) to prevent hard water buildup which will then cause inaccurate readings.

[4] Nitrate Test Kit; Nitrates are best under 30-40 for marine fish aquariums and under 20 (even less if possible) for reef aquariums

[5] Calcium Test Kit; this takes the place of the GH Test Kit in freshwater.
Calcium is important to ALL marine life (this includes freshwater too as it is often sadly overlooked), however it is absolutely essential for proper coral growth in marine aquariums. Bio-availability is also essential, Sea Chem Reef Calcium Polygluconate is probably one of the best, most bio-available calcium supplements available for marine aquariums.
Your marine Calcium levels should be between 400-450 ppm

[6] Nitrite Test Kit this should be 0 as in FW

[7] Dissolved Oxygen Test Kit; This kit although not essential is very useful, especially when you suspect over crowding or problems seem to reoccur. Saltwater (depending on salinity) holds roughly 42% less oxygen than freshwater. Warm water is much less capable of holding oxygen gas in solution than cool water. For example, water that is 90°F can only hold 7.29 ppm DO at total saturation, whereas water that is 45°F can hold 12.13 ppm DO at total saturation. A dissolved oxygen level of 5-7 ppm is sufficient, the first signs of stress in fish will show if the DO drops below 4 ppm, fatalities will occur at 2 ppm.
These problems will affect Dissolved oxygen (Freshwater or Saltwater):
*No or too little water agitation (via the surface)
*An overstocked tank, which results in larger amounts of waste (bio load) created that in return requires more bacteria to oxygenate the waste.
*Over feeding
*Waste rotting in the filter or in the gravel (common under rocks, in Wet-Dry and Canister filters)
*Green and cloudy water

[8] Magnesium Test Kit; Magnesium is an essential part of chlorophyll, which is necessary for photosynthesis, plants, including algae and the corals. Maintaining a correct magnesium concentration is very important, and is indirectly responsible for fast coral and calcareous algae growth by virtue of making the maintenance of correct calcium and alkalinity figures possible. Magnesium is depleted by algae and by the use of excessive Kalkwasser. Magnesium is what binds Calcium Carbonate in solution, if levels are low useable calcium levels will also drop. Poor choices of Marine Buffers can further exasperate this problem, this why I STRONGLY recommend Sea Chem Marine Buffer for adjusting alkalinity in marine aquariums (and EVEN freshwater aquariums) as this product has Magnesium, Calcium, and sodium bicarbonate in the proper ratios.
Magnesium levels in marine aquariums should be between 1200 and 1400 ppm.

[9] Iodine Test Kit; This test kit is important for reef aquaria, especially corals, both soft and hard. Iodine is present in natural sea water in a very low concentration (0.6 mg/L or 0.06 PPM) and this iodine occurs as several different species including iodide, iodate, molecular iodine and hypoiodite. It should be noted that time released iodine supplements or supplements containing organically bound/complexed iodine species will give false results with iodine test kits

[10] Strontium Test Kit; This test kit is important in accelerating the growth of coral and calcareous algae. Natural sea water contains approx. 7 - 9 mg/L strontium. Strontium is very difficult to test for, but if there is found to be a depletion of calcium in the aquarium then strontium levels are likely to be very low as well. Strontium concentration should be kept between 5 and 20 mg/L.

[11] Silicate Test Kit; Although listed in the saltwater section, this test kit can also be useful for testing silicates in freshwater as well, especially where Brown Diatom Algae is a continuing problem. Most silicate test kits are designed to test for silicates down to .2 ppm (mg/L). Natural seawaters contain silicates around 10 ppm however due to differences in a closed system (which an aquarium is) and the ocean it is best to maintain silicates under 1 ppm in an aquarium to prevent diatom blooms and aid in uptake of essential elements such as Strontium by corals.
In freshwater, silicates are generally between 4-20 ppm and should be kept under 4 ppm in an aquarium, although usually this is not a problem in healthy established freshwater aquariums where lighting is good to encourage plants or green algae (both of which will starve also consume silicates limiting diatom growth)


[12] Redox Meter; as in freshwater, I recommend -300 mV, except Redox is more important in marine aquariums.

[13] Phosphate Test Kit; as in freshwater this should near 0. High phosphate levels in marine aquariums can play havoc with the health and growth of live coral (Phosphates can block the absorption of important minerals).

For more about marine/saltwater aquarium keeping, please read this article: Marine/Saltwater Aquarium Keeping Basics & Information

For more about aquarium test kits, please read this article:
THE TRUTH ABOUT WATER FOR AQUARIUMS AND PONDS, AND ABOUT WATER TEST KITS

SEXING FISH; The differences between males and females (if any).

This depends on the fish, for many this can be very difficult.
I would also like to point out that although some articles here at Aquarium Answers are intended to be more in depth, this article is intended to just cover the basics and advanced aquarists will need to seek further information elsewhere. I provide several links to other sites and articles for more expanded information, please check them out as well.

Also several factors go into any fish developing into a breeding condition, where sexing the fish is more likely; water temperature, water quality, and a very important aspect is proper nutrition.
For more about proper nutrition:
Quality Fish Food; What ingredients are needed for proper fish nutrition, growth and health.


Here are a few basics:

Livebearers:
In Livebearers such as platties the male has a short tube called gonopodium in place of the anal fin, while the female has a normal triangular anal fin.











Guppies more transparent bodies (although many other light colored livebearers are similar here) are easier than many livebearers to see fry development inside the female.
Signs that your guppy or other livebearer is about to give birth include a large belly, a box like look from the front view, and a darker gravid spot which is under the pregnant females tail, which many identify as a stained glass window where the fry come out. As the babies near birth you can sometimes see eyes of the unborn fry as tiny black dots.
Click picture of guppy to enlarge

The gestation period in livebearers, which the interval between fertilization and live birth can vary, however as a generalization this time period is about 4-6 weeks at 78 F. The size of the brood can also vary greatly.
Most livebearers prefer water higher in mineral content and although salt is not required by most livebearers, it can be helpful as well. Keeping optimum conditions including proper mineralization as well as supplementing their diets with frozen/live/FD foods along with quality flake foods (I would strongly suggest foods high in spirulina such as Spirulina 20). As for the fry, I have achieved phenomenal success by simply powering Spirulina Flakes (at the time of most of my livebearer breeding, of which I had several tanks of Platties alone, I was using Green Flake Plus which is currently not available, but similar products such as Spirulina 20 still are). I also would supplement them with frozen baby brine shrimp o microworms.

Most livebearers of both sexes will eat their young so separation of all other fish is best and the use of a heavily planted aquarium (live or fake) or breeder trap for the female is advised.
Both swords and platties are capable of cross breeding as are Mollies and Guppies.

For further information please read my article about the care of Mollies (of which the care for other livebearers is similar): Aquarium Answers: Keeping Mollies in an Aquariums

Here is another good source for livebearer information: A Livebearer Primer

Cichlids:
In Cichlids some species, males and females are readily distinguishable by color, size or shape. For others it is difficult or even impossible to tell the sexes apart in non breeding individuals.

• Body shape: The male form a pair of cichlids in the wild is generally larger than female. Some females are larger than some males especially if not found in a breeding pair, so size alone is not a reliable indicator. Males may have a hump on the forehead. The size and shape of this hump differs by among species. This again is not foolproof as females in aquariums have also grown humps, so the presence of a hump does not in itself identify a male. Females may also rounder.
• Fin length: Males Cichlids will often have longer, more flowing and pointed anal and dorsal fins. This method has many exceptions too (such as female Convict Cichlids).
• Coloration: This is a species specific check for the sex of the fish. A few examples: (1) female convict cichlids have orange on the belly, particularly when they are ready to breed, while males lack the orange. (2) In Auratus African cichlids from Lake Malawi, the young fish have female coloring of a yellow-golden base with three black bands, aligned with white stripes running parallel to these black bands. As the fish mature the males reverse to a black base body color with yellow or turquoise bands. (3) In Kenyi African cichlids from Lake Malawi, the male and female start as basically a “blue” fish with stripes (there are subtle differences) and the male develops a more yellow golden background color while the female remains blue (see photo above left courtesy Eve).
(4) In Yellow Labidochromis African Cichlids (also from Lake Malawi) the male will often have a darker black border on the edge of there Dorsal fin, while the female is much less noticeable. Also the male Lab. May have an “egg spot” (or dummy spot) on his anal fin (please see the phot0 to the left, also courtesy Eve)
• Breeding Tube (Papilla): This is the only accurate way to sex angelfish and even this method is not always easy and can only be performed on mature angelfish. In the female angelfish the breeding tube is kind of stubby while in the male the breeding tube is more pin like (& difficult to see IMO).

Here is a tip as to determining Mbuna African Cichlids from Jon V. (from "Everything Aquatic"):
"When you get a group of fry or brood, keeping them in their own grow out tank for about a month. During this time as you feed fry foods, watch the group to see who's getting the most of the foods. Even at that early age, I've seen a tendency which I think is noted in other forums, that males will even be aggressive for food as early as the first few days when released. After about one month of this, you can take a brood of say about 20, and the ones that have already grown out larger then the others, you have about a 75-80% chance, those are males. While I've seen on some occasions, females grow rather large early on, I find this has great accuracy when comparing the first and second months of age."

For more about sexing cichlids (from Ron Coleman’s Cichlid Research Site):
Cichlid Research- Sexing Cichlids

For more about Angelfish:
Pterophyllum scalare (Angelfish)


Goldfish:

Sexing Goldfish is very difficult before they reach sexual maturity.
One way to tell is by looking at the shape of the vent. Females may have rounder convex vents while males have thinner concave vents. The pectoral fins of males may be rather thick and stiff (compared to those of female goldfish) and with a more pronounced outer ray.
Another way to tell is by male goldfish will developing breeding stars on their gill covers and along the first ray of their pectoral fins when they are ready to breed.

For more about sexing goldfish:
“Goldfish Basics”
The Gab; Sexing Goldfish


Bettas;

Male Bettas in the wild are short finned, so fins are not as reliable a way to tell the sex in bettas and is common belief.
Here are a few ways to improve the accuracy of sexing your betta:
(1) While looking at the male betta head on, there is an extra flap of skin under his body. The extra skin is an extended flap of skin from the gills.
(2) Again look head on, the males will have a much bolder head and fin structure.
(3) While a little less accurate, a male will generally not have a white dot under his body, in between his ventricles. Females will have this white dot.
Taken together you can give a much more accurate assessment of your Bettas sex.

For more about breeding and sexing Bettas:
BC Aquatics; Sexing Bettas
Or for more general Betta breeding information see: BC Aquatics; Betta Breeding 101


Gouramis;

Cousins to the Betta, both have a labryinth organ, which allows them to breath air directly. Both also come from SE Asia.
Many Males can be differentiated from females by the shape of the dorsal fin, which is long and pointed in males, compared to the females' shorter and more rounded dorsal fin. Females that are prepared for spawning will show a pronounced swelling in the breast area, while the male will be more slender in the breast area. In many Dwarf Gouramis, the males are much more colorful than the females (this is not usually true from my experience with other Gouramis such as blues).
Please note that these are generalizations and do not apply to all Gouramis.


Currently I have not found any in depth articles about Gouramis (other than species specific) that I can recommend. Either I will write one at some point in the future (as I did for mollies) or is one is brought to my attention that is NOT from wikipedia or some other sites that specialize in anecdotal information, I will post it.



FOR MY FULL AQUARIUM INFORMATION ARTICLE:
AQUARIUM AND POND INFORMATION; Well researched and up to date aquarium and pond answers, help, and links

What is a Chocolate Chip Starfish - (Protoreaster nodosus)
Also information about Knobby and Fromia Starfish


A Chocolate Chip Starfish (Protoreaster nodosus) are found in warm areas of the Pacific Ocean, Indian Ocean and the Red Sea. They live in shallow tidal pools and reefs up to 100 feet deep. They feed on sponges, bacteria, waste products and the remains of dead plants and animals. Chocolate Chip Starfish hunt with their sense of smell.

Chocolate Chip Starfish are popular aquarium starfish due to their low maintenance, hardiness and low price. Other popular aquarium starfish include the Knobby and the Fromia Family of starfish which includes; marbles, reds and blues.

Feeding:
Starfish eat with a mouth not visible from above. Their mouth is actually on the underside of the starfish's body. In order to pick up the food they consume, they cover the food with their body and push out their stomach from the inside.
In the aquarium they are basically a scavenger, although often make sure they eat by placing them on a cut piece of fish or similar.

Compatibility/ Care:


Chocolate Chip Starfish as well as the Marble Starfish are mild to medium aggressive and will go with many fish, but not with triggers and a few other predatory fish. They are OK in a Nano reef WITHOUT corals or delicate anemones. CC Starfish are fine with Hermit Crabs, Turbo snails, Feather Dusters and less delicate anemones such as Long Tentacle Anemones.


The Fromia family of starfish are more reef compatible with delicate anemones and corals (although I stll advice some caution). The Reds, Marbles, Blues and others that make up the Fromia family are NOT as hardy in my experience and should NOT be added to a new marine aquarium, I personally advice waiting about 3 months.

The Chocolate Chip and Marble starfish can be added sooner and are less delicate, however these are still not the best “first” inhabitants in a marine aquarium in my opinion.



Breeding:

Starfish spawn which means they release eggs and sperm into the open ocean at the same time. Females can produce up to 65 million eggs per spawning season. During spawning season thousands of starfish gather and release sperm and eggs into the ocean. The egg and sperm join and produce many tiny sea stars which float in the water like little blobs that later form into a star shape.
They can also asexually reproduce. They also can regenerate their body. If another creature attacks the starfish and eats or tears off an arm they can regenerate arms. As long as the main body is not injured they can re-grow.

Here is the full classification of Chocolate Chip Starfish:
Category: Saltwater Invertebrates
Kingdom: Animalia
Phylum: Echinodermata
Class: Asteroidea
Order: Valvatida
Family: Oreasteridae
Genus: Protoreaster
Species: nodosus

For more Marine information:

Marine Aquarium Basics; Fish and Nano Reef

Saltwater Fish and Invertebrates


For Aquarium Multi Skimmers
Aquarium protein skimmer, filter and UV sterilizer combination.