This glossary is just a helping hand, with some useful word descriptions in connection with the freshwater fish hobby.

Acidicty: This is a water condition in your aquarium. Hydrogen ions in the water makes it more acid. And its nothing about the 60's and hippies, honest.
Aeration: The introduction of air. See Air pumps
Air pumps: This is a continous supply of air. See Aeration and Filtration.
Algae: This is a very basic type of plant in a aquarium, and bloody annoying. There are many types, you can remove it by brushes, scrapers, and chemical treatments can be used, but will also affect your other plants in your tank.
Alkaline: This is a water condition in your aquarium. Hydroxide ions in the water makes it more alkaline.
Ammonia: This is the chemical compound NH3 (Nitrogen, hydrogen) which is one of the first compounds in your new aquarium. See The Nitrogen Cycle
Aerobic: Living with oxygen.
Anabantoids: Click here to see pictures and info.
Anaerobic: Living without oxygen. This is a living situation most commonly associated with "bad" bacteria.

Beneficial Bacteria: There are useful bacterium in your aquarium, like Nitrosomonas which will convert ammonia to Nitrite. See The Nitrogen Cycle
Biological filtration: This system breaks down any toxic compounds, usually Nitrogenous toxins. The Nitrogen Cycle
Brackish waters: Water tha is mainly freshwater, but also contains smaller amounts of salt.
Brime shrimp: Becoming very popular with the average aquaritics, high in protien and nice snack for many freshwater fish.
Bubble Nest: A term used for a nest which is suspended by a weave of tiny air bubbles. It is used as a protective coating for the eggs and the newly hatched young. It is most commonly used by the anabantids.
Buffer: A substance used to treat the water and to counteract changes in the pH.

Cannister Filter: A filter which pushes water through an external canister which contains a filter media such as filter floss, polyester or carbon.
Carbon: Activated carbon medium in your aquarium helps to break down dissolved substances in the water.
Carbon dioxide: Known as CO2, is the biproduct from respiration. If you wanted to keep real plants in your aquarium, CO2 is one of the elements needed - Photosynthesis.
Catfish: Click here to see pictures and info.
Chlorine: Aggh!! The enemy to any freshwater fish, chlorine is very toxic to the fish. Use water conditioners to remove it.
Characin: Click here to see pictures and info.
Cichlid: Click here to see pictures and info.
Cloudy water : Everyone today seems to have their water more foggy than the Thames - the cause is normally because of a rapid development of bacteria and algae spores. This in turn is often because of the The Nitrogen Cycle
Cyprinids: Click here to see pictures and info.

dGH: Water hardness is expressed in degrees of hardness. 0 - 30 is normally used, 0-4 being very soft, 5-8 soft, and so forth until 30 which is extremely hard water. Look at "Water hardness".
Diseases: Dropsy, Whitespot, fin-rot, Fungus - these are just some of the more common diseases that a fish can be attacked by. See my Diseases table.
Drip loop: A way of making sure that water doesn't travel along cables to an electrical outlets. For more details, see Hints and Tips.

External filters: Pretty simple, a filter which is located outside of the tank.

Filtration: With no filtration, there would be no aquarium. This process removes waste materials from aquarium water.
Filter medium: These trap suspended waste as the water is passed through the filter.
Fishless Cycle: Instead of using a few hardy fish to start off the cycle, there is an option to use liquid ammonia. A useful article can be found at - Fishless cycle . Note: This is noy my article.
Freshwater: Water with no salt content.
Fry: Baby fish, can be very small and need special attention.
Flakes: A great source of food for almost any fish.

Gravel: Basic bedding for any aquariums, make sure you have enough in your tank.
Gonopodium: An modified anal fin which is elongated. Only appears on the males, which helps to fertilize the females. You would expect to see these organs in Livebearers. Go Livebearers!!

Heater: Needed to heat the aquarium to the appropriate water temperature. 24 Celsius is the average for many tropical freshwater fish.

Impeller: An electrical impeller, which pumps the water through the filtration system.
Internal filter: A filter which is located inside the aquarium.

Killifishes: These are fish with a low life-span, often only for a year. Sods law, they are also some of the prettiest. Click here to see pictures and info.

Labyrinth fish: Fish which are also called Anabantoids.
Livebearers: These fish are fertilized and hatched within the body, which means they are easier to breed. Click here to see pictures and info.

Medication: There are many fish medications to cure illnesses on the market, and many are very useful.
Mechanical filtration: A way of trapping any waste materials from the aquarium water. See Aeration and Filtration.
Milt: I shall say nothing but what it is: Sperm.

Nitrate: A toxin at the end of the nitrogen cycle in your tank. The Nitrogen Cycle
Nitrite: A compound which is intermediate during the Nitrogen Cycle.

Peat: Peat is a moss which can be used to soften water and to decrease the pH. It can also tint the colour of your water.
Phosphates: A byproduct of fish and inverteabte metabolism and decaying organic matter, such as uneaten food. Can cause algae problems if you have high levels.
pH: A measurement of the acidity or alkalinity of your water.
Plants: Plants come in different sizes and shapes, you can use plastic or real plants. For more details about real plants, look at Tropica.
Power filters: This is a filter which uses a high water flow rate.

Spray bar: Many use these - e.g. if you had a very strong powerhead, a spray bar can disperse the flow across the bar.
Substrate: Material used on the aquarium bottom. Examples include gravel, sand, etc.
Stress: Bloody right, making a mistake during a water change is stressful, without doubt. But fish can be stressed, take care of them.

Tannin acid: You have added bogwood to the tank - and the water has turned orange? Its because the wood has leeched its tannin acids into the aquarium - a good boiling and soaking in a bucket for a few weeks, will remove the problem hopefully.

Vacuum: Can be used to remove water during a water change (syphon), and can clean the gravel and remove wastes.

Water: The great H2O, the water is the basic ingredient in your aquarium. Using test kits will rate your water.
Water hardness: Water hardness refers to how much Calcium and Magnesium is in your water. Water rich in Calcium salts is considered "hard".
Water-turnover: The rate at which water flows througha certain filter. This is normally rated at LPH (Litres per Hour). In general, water turnover in an aquarium will be 3 to 4 times the tank capacity an hour.

Zeolite: An ammonia removing substance.