I - Aquarium and Fish Dictionary

Aquarium Fish Definition and Glossary

Ichthyologist :: Icthyology is the study of fishes. An Ichtyologist is the person that does the studying. An Ichtyologist could work for a large aquarium, a museum or a university identifying fish species and documenting fish behavior and habitats.
Inch Per Gallon :: refers to a rather silly guideline you'll come across that some hobbyists use to stock their aquarium. This "guideline" recommends stocking 1 inch of fish per 1 gallon of water. This is an extremely short sighted rule and only works on very small or juvenile fish. Larger fish species require much larger living quarters. A 1 inch pacu will not last long in a 1 gallon aquarium. Various factors come into play when stocking an aquarium such as fish temperament, how large the water surface is for gas exchange, the type of filter system used, water change regimens, etc. Please don't follow or believe this rule!
Infusoria :: are tiny organisms (protozoa) and algae that are cultured (grown) and fed to fish fry.
Ich :: also known as ick or white spot disease, Ich is a very common fish disease. The freshwater ich version is Ichthyophthirius multifiliis and the saltwater ich version is called Cryptocaryon. It appears as small white dots all over the fish's skin. It's actually a parasite that is just below the skin. Ich has a life cycle that consists of a free-living stage and a parasite stage when it attaches to the fish. After it has been attached to the fish for a while, it will break free and settle into the substrate where it will become a cyst, reproduce and multiply many times over. When these cysts mature they can swim and start looking for a fish host. This is a common disease and should be taken seriously if you want to save your fish. It has the capacity to wipe out entire tanks if not treated. There are many products on the market to treat this parasite. Please use a quarantine tank for any new arrivals to prevent an ich outbreak. Also see: Fish Disease.
Internal Aquarium Filter :: any filter that needs to be operated inside the tank. Examples of internal aquarium filters are the undergravel filter, sponge filter and corner filter.
Invertebrate :: animals that do not have a backbone. In aquariums, invertebrates are snails, shrimps, crabs, corals, anemones, etc.
Iodine :: a saltwater aquarium supplement, iodine is used up quickly by the tank inhabitants (corals and invertebrates) and skimmed from the tank via the protein skimmer. It is crucial to use an iodine test kit before dosing iodine in your aquarium. In natural sea water, the iodine concentration is 0.03 - 0.06 mg/L (ppm).