7.2.14. BioHome Filter Media

BioHome does not work well and is hugely overpriced. Biohome does very poorly at ammonia removal and does NOT do ANY removal of nitrates.

10.13.5. Bryozoans and Stentors

Bryozoans One interesting little critter that looks much like a hydra but is a different type of animal is something called a “bryozoan”. It acts and looks much like hydra but tends to occur in clusters and colonies, often quite large. It is very rarely seen in the aquarium. The little bodies have many more … Read more

17.11.4. Food for Discus

University research has shown discus are somewhat less forgiving than most fish when it comes to fish food. Commercial dry foods generally are not “optimum” for discus, even if they have a label that says “For Discus”. But note the word “optimum”. Perfectly satisfactory results can be had with most pelleted commercial fish food as … Read more

17.11.6. Breeding Discus

Breeding discus is a very misunderstood topic. It all has to do with what black water is. The native waters of discus are typically “black water” biotopes. Black water is water which is so low in dissolved solids that bacteria cannot grow. Bacteria need some sodium chloride and other salts in order to metabolize well … Read more

17.11.5. Discus Pheromones

A pheromone is a chemical that an animal produces which changes the behavior of another animal of the same species. Think of a pheromone as a “smell”. These “smells” can be very complex and have a lot of components. There is one large supplier of discus which started out their huge discus breeding faculty with … Read more

17.11.3. Water for Discus

Many think that discus MUST be kept at a high temperature 84 to 90°F (29 to 32°C) in water which has a low TDS and a pH between 6.0 and 7.0. This is ONLY true if one is trying to raise competitive discus which are as large as possible. Adult discus in a decorative aquarium … Read more

17.11.2. Filtration for Discus

I found the key to decorative discus is ultra-crystal-clear water with NO bacteria counts and a HUGE amount of biofiltration. And I mean HUGE!  For decorative discus one should ideally have a sump of at least 40% of the aquarium size (a 50 gallon (189 liter) aquarium needs at least a 20 gallon (75.7 liter) … Read more

17.11.1. Discus Husbandry

The “optimum conditions” for DECORATIVE discus are: But note these are “optimums”. Very fine, healthy, attractive DECORATIVE discus can be raised well away from these optimums as long as the water is low in bacteria. Tankmates for Discus Discus typically are kept in a species only tank. But some like some other fish in with … Read more

17.11.7. Discus Photos

Here is a page of photos of discus tank which will give one an idea of how varied the selection of discus breeds can be.

15.5.2. Fertilizer Programs

There are several worthless programs that use a complex of five or more components to supposedly make a good fertilization program. It is all marketing hype.

18.1.4. Softened, RO, DI, TDS

Any water you can drink is fine for almost any fish.  Plants are a little more touchy. The only time one can have problems is: So any sort of water treatment beyond chlorine conditioner is normally just a waste of money. But many want to know the options so here goes: Water Treatment in Depth … Read more

16.2.7. Chihiros Doctor

Many planted aquarium photos from Europe show a little fan-like device in one corner. These are the “Chihiros Doctor” (the Twinstar Unit is very similar and does the same thing). The units are somewhat expensive ($73 to $110). This device supposedly controls algae. This device is nothing more than a “sneaky” way to use chemicals … Read more

15.6.4. CO₂ From Food

There is one “interesting” approach to providing carbon dioxide to the aquarium which bears mentioning. This is to use food as the source of CO₂. Note I do NOT recommend this method. It is challenging, to say the least. Let’s do some simple math here. In a planted aquarium it is desirable to add VERY … Read more

16.2.6. Chemical Algae Control

We do not recommend chemicals to treat algae. The two photos above were posted to an aquarium forum in Facebook. The show what API Algaefix did to a tank. It killed every fish. This is VERY common. Any chemicals (save antibiotics for “blue green algae”) which kill algae are “disinfectants” that will kill ANY cell … Read more

16.2.5. The Algae War

Summary This is only for planted aquariums. If you have a fish only aquarium ignore this article. It is very important to plant a planted aquarium with a LOT of plants. There needs to be a plant of some sort every three inches. To illustrate, a 20 gallon aquarium is 24 x 12 x 16.  … Read more

16.2.4. Algae Eaters

A very good way to treat nuisance algae is by using “algae eaters”. These include sucker catfish such as bristlenose catfish (ancistrus), otocinclus, flying foxes (Epalzeorhynchos kalopterus), Silver Flying Fox (Crossocheilus reticulates) and Siamese algae eaters (Crossocheilus siamensis). Black mollies and redline sharks also eat algae. Shrimp and snails also eat algae. These can be … Read more

16.2.3. Algae in Low Tech Tanks

By the terms “low tech planted aquarium” we mean an aquarium with vascular plants but no carbon dioxide injection. In these types of planted aquariums heavy algae growth can be prevented by several means: Because vascular plants have lots of carbon filled cellulose in their structures, they need more CO₂ than simple algae needs. And … Read more

16.2.2. Algae in High Tech Tanks

We define a “high tech planted aquarium” as a planted tank with carbon dioxide injection and high intensity lighting with some crimson and blue light. There are a whole list of things needed for the good growth of higher plants in the high tech planted aquarium: Algae control in high tech planted aquariums is surprisingly … Read more

16.2.1. Algae in Fish Only Tanks

To control a severe algae outbreak in a fish only aquarium it is best to simply do some six to eight 50% water changes over the span of two days. Contrary to popular mythology, large water changes are perfectly natural (a fish swimming in a river has a water change every second) and harmless to … Read more

15.5.3. Estimative Index

These are instructions on how to use the estimative index fertilizer program for planted aquariums.

18.1.3. Water Change Water

Newcomers to the hobby are bombarded in the fish store with all sorts of water treatments: conditioners, stress coat, pH adjusters, ammonia detoxifier, bacteria in a bottle, buffers, aquarium salt, ad. infinitum. Only a cheap conditioner is necessary. All the other products are simply scams. When it comes to water this is the “Rule” If … Read more

18.1.2. Aquarium Water Change Math

There is a “rule” that says you need to change the water 50% every week and a 25% change twice a week with an aquarium. The only reason for doing water changes is to keep the nitrates down. Note there are all sorts of other reasons given on social media for doing water changes: “You … Read more

18.1.1. Water Changes in Depth

It is generally (but not universally!) accepted that fish will do better in an aquarium if some of the water is drained upon occasion and replaced with new clean water. This is called a “water change”. People drain and refill anywhere from 75% of the aquarium twice a week to 10% of the aquarium every … Read more

15.5.4. NH₄ and Tabs Fertilizer

These are instructions on how to make the optimum planted aquarium fertilizer by using ammonium salts and phosphorus and iron additions to only the substrate.

15.6.5. Liquid CO₂

There are a whole series of products which supposedly add “liquid carbon” to a planted aquarium. There are three points which summarize the discussion: To go into more depth read on. “Liquid Carbon” in Depth There is one supplier which is honest about “liquid carbon”. It is Cory at Aquarium Co-op. Cory is the most … Read more

15.5.1. Ready Made Fertilizers

The easiest approach to planted aquarium fertilizing is to simply use Aquarium Co-Op Easy Green™ per the instructions on the container.

10.4.2. Mycobacteriosis in Humans

Fish TB or mycobacteriosis can infect humans and is a serious disease not to be taken lightly. All hobbyists should know the symptoms.

14.2.2. Gravel

Gravel is probably the best all around substrate for aquariums.

16.10.1. White Fuzz

There are a whole host of ways in which water molds and other “white” organisms can present in the aquarium. The terms for such “fuzz” include fungus, mold, slime, tufts, coating, cotton, white streamers, fog etc. Most of these white fuzzy growths are species of “water mold” (order Saprolegniales, generally from three genera: Achlya, Leptolegnia, … Read more

2.8.2. Sludge Removing Bacteria

There are products which are supposedly “sludge removing” bacteria-in-a-bottle. These include Seachem Pristine™, Tetra Cleaning Bacteria™, API Stresszyme +™, Fluval Biological Cleaner™, Nutrafin Waste Control™ , Outbreak!™, FritzZyme® MONSTER 360™ and Dr. Tim’s Waste Away™. They are the very definition of fraud. “Definition of fraud; DECEIT, TRICKERY, specifically: intentional perversion of truth in order to … Read more

4.8.1. Rapid Thermal and pH Shifts

The going mantra is that tropical fish require “stability” and “constancy” of pH and temperature. Supposedly any rapid change over 0.2 pH or 2 degrees temperature will “shock”, “stress” and possibly kill the fish. This idea is a myth. Experimentation and scientific research by the author and Universities has shown this to be patently false. … Read more

17.5.4. Goldfish Care

Goldfish, due to hundreds of years of “inadvertent selective breeding” are simply the easiest fish there is to keep. Yet well meaning but ill-informed individuals on social media will tell the hobbyist that goldfish are very touchy fish that requires a great deal of careful care. This is because of a concerted effort by PETA … Read more

17.5.3. Stocking Goldfish

Stocking for goldfish (i.e. the number of gallons needed for each goldfish) is controversial, to put it mildly. But it all can be summarized in one bullet: . It all boils down to an OPINION . It is the OPINION of many hobbyists that goldfish need very large aquariums in order to “thrive”. It is … Read more

17.5.2. Size of Goldfish

In a small aquarium a common goldfish will grow to possibly four inches and no greater. In a large lake a common goldfish will normally grow to six inches with an occasional fish getting to eight inches. If you want a bit of a rant followed by a very long and boring analysis of the … Read more

17.5.1. Types of Goldfish

There are two distinct types of goldfish. The common, sarasa and shubunkin goldfish are one type of goldfish, which some call “narrow bodied goldfish”. These fish are easily kept under many different conditions, including overcrowded, small tanks with poor water quality. They can live to be 20 or even 30 years old. “Fancy goldfish” or … Read more

8.1.1. Filter Test

An article on a test of various aquarium filters as ammonia oxidizing devices.

8.7.6. Small Filters

There are several different designs of filters commercially available for small aquariums.

7.1.1. Cost of Filter Media

If one adds in the cost of more filters needed for poor media the cost differential between the most cost effective media and the least cost effective media becomes a factor of 25.

7.1.2. Media Function

Aquarium filter media should be designed to provide a very high surface area for colonization by populations of nitrifying bacteria.

5.2.3. Ammonia Spikes

Most home hobbyists measure the total ammonia via the API “Ammonia” test kit. This test kit measures both ammonia gas and ammonium ions. It is not unusual for a hobbyist to be surprised by a sudden unexpected spike in these numbers. It is not cause for concern most of the time. Ammonia+ammonium spikes and nitrite … Read more

17.4.1. Malawi Aquariums

These are examples of Lake Malawi aquariums pulled off social media. Note that they are all heavily stocked. Heavy stocking is the key to keeping a good Lake Malawi aquarium. This illustrates that Lake Malawi cichlids do best with very heavy stocking. Very heavy stocking reduces aggression. These aquariums all had very good filtration. If … Read more

14.2.3. Buffering Substrates

It is beneficial for most aquariums to add a bag of crushed coral to the filter. This buffers the water to 7.6 to 7.9 pH. This pH is great for all fish, contrary to popular mythology.

14.2.1. Sand

Sand and blasting media are great substrates for the aquarium.

5.5.3. Water Conditioners

Most water supplies in the developed world have either chlorine or chloramine in them to kill bacteria and prevent disease outbreaks. This chlorine and chloramine need to be neutralized before it gets to the gills of a fish as it is very toxic to the fish. This is done with something called a “conditioner”. All … Read more

12.4.7. Quinine

One very typical example of the profit motive at work is the promotion of Chloroquine Phosphate as an ich medication. The claims put out by the manufacturer of the product, as usual, combine fact with fiction in a blend that deceives many people. The manufacturer claims Chloroquine Phosphate kills the malaria organism, a true statement. … Read more

12.4.6. Furan and Sulfa

Sulfa and Furan Drugs Sulfa and furan drugs do not treat fish diseases very well. They should be thought of as antiseptics which have limited bacteriostatic actions when dissolved in the water column of an aquarium. They will stop the transmission of bacteria from one fish to another fish. They are far more effective when … Read more

12.4.5. Antiseptics

There are many medicines marketed for fish diseases which are properly termed antiseptics (other terms are disinfectants and antibacterials). These are frequently touted for use in fish for treating fish diseases. The following antiseptics are commonly touted for treating fish pathogens: They all have been touted as being good to use in solution in a … Read more

12.4.4. Formalin

Some medications use a compound called formalin in them. Formalin is simply a 30% solution of formaldehyde, the stuff which preserves frogs for dissection. Believe it or not, this compound supposedly kills all the following pathogens; In actuality this is true. At a high enough concentration formalin kills the exposed living cells of all these … Read more

12.4.2. Salt

As a medication, salt has very limited uses in the aquarium.

12.4.1. “Natural” Aquarium Medications

There are a whole host of aquarium medications which are labeled as “Natural”. Sorry, I just cannot sugar coat this: “Natural” Medications are ALL Worthless . ALL the claims made for “natural medications” on social media are simply parroted marketing hype designed to make money.  I.e. they are all simply “snake oil” and will not … Read more

11.1.2. Spots on Head

White tufts on the head of a fish is a syndrome called canal neuromast inflammation, a form of hole in the head syndrome.

7.4.8. Chemi-pure

There are several varieties of a “Proprietary Product” called Chemi-pure. These are simply mixtures of the products below with very high price tags: So if you want to do some of the above things and pay a huge amount of money to do them, be my guest. Buy yourself some Chemi-pure! If you want further … Read more

10.13.3. Planaria

Aquarium planaria are discussed in depth, including how to control them.

10.3.9. Red Gills

Red inflamed gills are typically infected with a gram negative bacteria and the fish need an antibiotic in the food and ONLY in the food.

10.3.8. Popeye

Popeye is typically a gram positive bacterial infection and the fish needs an antibiotic such as erythromycin in the food and ONLY in the food.

10.3.7. White Eyes

A tropical fish with one or two white eyes has a bacterial infection and needs antibiotics in the food and ONLY in the food.

10.3.6. Red Blotches

When a tropical fish gets red blotches on its body it is a internal bacterial infection that requires antibiotics in the food and ONLY in the food.

10.3.5. Saddleback

When a white patch appears on the back of a fish it is a bacterial infection called “saddleback”. It requires antibiotics in the food and ONLY in the food.

10.3.4. Fin Rot

Fin rot is where the fins of tropical fish erode away, typically with a white edge. It requires antibiotics in the food and only in the food.

10.3.3. Duck Lips

Very fat lips in an aquarium fish is normally a sign of a serious bacterial infection.

10.3.2. Mouth Rot

When the mouth of a fish starts eroding away this is a bacterial disease called mouth rot.;

10.2.7. Cryptobia

Cryptobia can be suspected if large numbers of cichlids are dying with few symptoms in the matter of a few weeks.

10.2.4. Epistylis

Epistylis is a very common and very unrecognized fish disease. It is commonly confused with ich.

10.2.3. Velvet

“Velvet” (Piscinoodinium pillulare, or “oodinium”, a dinoflagellate algae) is a very small parasite that looks like tiny spots of yellowish to golden-brown or rusty-colored varnish on the fish. Well intentioned but ill-informed commentators on the social media are constantly identifying patches of white on fish as “velvet”. They are simply wrong. “Velvet” has a distinctive … Read more

8.9.2. A Feasible Reactor

It is possible to remove nitrates from an aquarium via anaerobic denitrification but we do NOT recommend it

8.9.1. Biocenosis Reactor

A critique of the false idea that a filter made of kitty litter can somehow help reduce nitrate to nitrogen gas.

8.7.2. High Performance Filters

High performance filters for the aquarium are simply very expensive commercial fluidized bed sumps. Don’t even consider them.

8.7.1. Sand Filters

Aquarium sand filters are too complicated in operation to be useful in most aquariums,

8.3.2. Do-it-yourself Canisters

Joey (the King of DIY aquariums) has a YouTube Video on making a do-it-yourself pipe canister filter. His was about four-foot-long (120 cm) and made from 4-inch (10 cm) pipe. This will give you about 2.6 gallons or 10 liters of room for media. Leaks can be a huge problem with Joey’s design (or any … Read more

8.3.1. Canisters in Depth

The biggest myth with canisters is that the flow through the canister is what is important. That is just plain incorrect. The test below showed that flow has very little effect on the efficiency of a canister. Test of Flow Rate in Canisters Canisters are normally rated by their flow rate. Supposedly if you double … Read more

8.6.7. Foam Sump

Foam in a sump makes for a very effective low maintenance aquarium filter.

7.4.7. Poly-Filter

Poly-Filter is an extremely expensive ($45 for a one square foot piece!) fibrous pad material which is commonly used in filters. Some breeders add this to the bags of fish shipments, supposedly to absorb or adsorb contaminants. It supposedly removes “Harmful Organics, Toxic Ammonia and Nitrite, Heavy Metals, All Forms of Phosphate, Medications after Treatment”. … Read more

7.4.6. Purigen

Purigen will NOT create clear water nor will it help with nitrates. Purigen will absorb colored compounds such as tannic acid.

7.4.5. Phosphate Remover

Phosphate removing granules work! Iron and aluminum phosphates are simply very insoluble. So, these products will remove phosphates from the water. The use of phosphate removing granules are indicated where a phosphate test indicates high phosphates are causing an algae bloom. “Blue-green algae” blooms are very commonly caused by high phosphate in the water. So … Read more

7.4.4. Zeolite

There is a mineral which selectively removes ammonium from the water. It is a zeolite called clinoptilolite. This can be found in the LFS as white granules. This material can remove about 1.74 mg NH₄–N g−1 (“Ammonia Removal from Leachate solution using Natural Chinese Clinoptilolite”, Wang et. al. 2006). A 100-gallon aquarium with 3 part … Read more

7.4.3. Ion-Exchange Resins

There are two distinct uses for deionizing resins. One is to treat water for a water change and one is to directly treat the aquarium water to remove nitrates or ammonia. Neither use is a very good use of monetary resources, to put it mildly. What is DI (Deionizing or Ion Exchange) resin? An ion-exchange … Read more

7.4.2. Activated Carbon

The activated carbon used in aquarium filters is elemental carbon, i.e. pure carbon with nothing else in the atomic structure. Activated carbon is typically lignite coal heated above the temperature at which it burns in an oxygen-free atmosphere. Since there is no oxygen, the carbon of the coal doesn’t burn. Instead there are a billion … Read more

7.2.12. Matrix

Seachem Matrix filter media is simply marketing hype that doesn’t work very well. This was confirmed by testing.

7.2.10. Growstone

“Growstone” or “Buddystone” is not a very effective media to put in aquarium filters.

7.2.9. Lava Rock

Testing has shown lava rock is NOT a good media to put in any aquarium filter.

7.2.6. PP EVA Pads

EVA pads are decent filter media for aquariums and ponds. Japanese mats are not good media.

7.2.2. Foam Media

Foam is a very good biomedia for aquarium filters, confirmed by testing.

7.2.1. Polyester Floss

Polyester Floss is usually only used for mechanical filtration. It is rarely used for biofiltration. This article goes into why polyester floss has to be used this way.

6.2.2. Brown Gunk

A lot of the science in any aquarium setup is involved with biofilms and biofloc.

5.3.2. Nitrite in More Depth

The recommended chronic exposure upper limit in the aquarium of nitrite in parts per million is dependent on pH as follows (from Duke University https://users.cs.duke.edu/~narten/faq/cycling.html): These limits are for chronic toxicity, where long term damage to internal organs occurs. There are some university papers on the toxicity of nitrites: The toxicity of ammonia and of … Read more

5.5.2. Chloramines

Chloramines are used to disinfect drinking water. Chloramines kill tropical fish even in very small amounts.

4.5.1. General Hardness

General hardness, GH, in the water basically reflect the amount of the elements Calcium and Magnesium one has in the water. Calcium and Magnesium is what forms scale and crusts in your toilet and bathtub tiles (and your aquarium). Calcium and Magnesium are elements which don’t dissolve very well in water. So, when given the … Read more

4.4.3. Carbon Dioxide and pH

CO2, KH and pH are the Bermuda Triangle of fishkeeping. Go there and you may never come out. It is a very complex and unpredictable relationship.

3.3.1. Amount in Depth

Over FeedingSince fish are cold blooded (poikilothermic), they do not require a lot of energy and food to survive compared to mammals. Overfeeding your fish can lead to problems. It leads to excess waste which will cause the biological load on the filtration system will become overworked. Continued overload can lead to the disruption of … Read more