Aquairum terminology reference.
Water Chemistry- These determine the quality of the water. The properties of most interest to the aquarium owner are; total hardness, carbonate hardness, non-carbonate hardness, ammonia, nitrate, nitrite, carbon dioxide, oxygen, pH, and temperature.
PH- (potential of hydrogen) The measuring unit indicating the degree of acidity of water. The degree of acidity or alkalinity is determined by the relative amounts of acids and bases in the water. If both are present in equal proportion (as in pure water), the ph is neutral or 7.
GH- (general hardness) The total amount of dissolved salts of calcium and magnesium present in a sample of water.
If there are more acids than bases, the water is acid (pH below 7). If bases predominate, the water is alkaline or basic (pH above 7). Aquarium waters are usually in the range of 6.0 to 8.5, depending upon the environment being replicated.
Ammonia- (NH3) A toxic substance that builds up in the aquarium, particularly in a newly setup tank. Ammonia is the first step in the nitrogen cycle, and is produced as a byproduct of protein breakdown such as, uneaten fish food and fish excreta.
It is removed by beneficial bacterial that are able to convert it into nitrite. NH3 occurs only in alkaline water, appearing instead as ammonium (NH4) when the water is acidic.
Ammonium- (NH4) The ionized form of ammonia, which is occurs when the water is acidic. It is not toxic to fish as ammonia is, which is why aquariums that have acidic water do not have as many problems with the intial phase of the nitrogen cycle.
Ammonium, the most important nitrogenous fertilizer for water plants, is essential for the breakdown of plant protein.
Nitrate- The end product of the metabolism of ammonia by nitrifying bacteria. It is only toxic to fish in very high concentrations. However, it is undesirable due to the fact that it promotes algae growth. Regular water changes and proper aquarium maintenance will keep the levels low.
Nitrite- An extremely toxic nitrogenous substance formed by certain bacteria in the process of ammonia oxidation in the aquarium.
Hardness, Degrees of- A device for filtering water that uses several ion exchange resins to purify and remove impurities from the water. Deionized water is often used in aquariums to lower the hardness and/or pH.
Hard Water- Water that contains dissolved salts of calcium and magnesium in a concentration greater than 200 parts per million.
Soft Water- Water that contains dissolved salts of calcium and magnesium in a concentration greater than 200 parts per million.
Nitrification- The process by which bacteria converts ammonia into nitrite, and then nitrite into nitrate. This is the basis of the nitrogen cycle.
Nitrogen Cycle- The natural process through which nitrogen incorporated into food by photosynthetic organisms is consumed directly or indirectly by other organisms and subsequently excreted, acted upon by bacteria, and made available again for plant nutrition.
In an aquarium the establishment of the nitrogen cycle is often referred to as the break-in cycle, start-up cycle, or cycling the tank. The cycle begins once fish are introduced to the tank.
Buffer- A substance dissolved in the water that maintains pH. Buffers may be formulated to adjust the pH to a particular value, or to alter the alkalinity without changing the pH. A solution that is properly buffered will resist a change in pH when either acid or alkali is added.
Acid- A chemical compound that dissociates in solution to yield one or more hydrogen ions; a solution with a pH less than 7.0. Many aquarium fish prefer slightly acidic water.
Acidity- The base neutralizing capacity of water. Acids contribute to corrosiveness, influence chemical reactions, and chemical/biological processes. Acidity is determined by using a titrametric or potentiometric method. In the aquarium the acidity is an important factor when providing the proper environment for the fish and/or plants being kept.
Peat Filtering- A method of chemical filtering that lowers the carbonate hardness and pH of the aquarium water. The filtering material used is peat. A rule of thumb is that 7 ounces (200 g) of peat will lower the hardness of 25 gallons (100 L) of water by about 10 dCH.
Alkaline- Water with a pH over 7 is alkaline, also referred to as basic.
Alkalinity- The measure of a solution's resistance to changes in pH. It is commonly measured as carbonate alkalinity or total alkalinity, and is expressed in meq, dKH, or ppm of C03 ions. Alkalinity can be raised by adding a buffer.
Salts- Chemical compounds made up of negatively charged particles. Many salts dissolve readily in water, breaking down into the ions they are made up of. These salts determine the hardness and electrical conductivity of water.
Sulfates- Sulfuric acids present in the water. They contribute to the non-carbonate hardness.
Carbonate Hardness- Also known as KH, refers to the concentration of bicarbonate (HCO3-) and carbonate (CO3--) dissolved in water. Hydrogen carbonates are easily soluble in water, while carbonates virtually insoluble. The level of carbonate hardness thus depends on the amount of dissolved hydrogen carbonates.
Carbonate hardness affects plant growth to a greater extent than does the level of non-carbonate hardness. Plants can dissolve carbon dioxide out of hydrogen carbonates and carbonates and use it for photosynthesis.
Nitrobactor- A bacteria once thought to be solely responsible for oxidation of nitrite to nitrate during biological filtration. Recent research has shown that other bacteria may also be involved.
Nitrosomonas- A bacteria once thought to be solely responsible for oxidation of ammonia to nitrite during biological filtration. Recent research has shown that other bacteria may also be involved.
Cation Exchanger- An ion exchanger that exchanges only the cations in the aquarium water, replacing them with acidity-forming hydrogen ions. It is suitable for softening water with high carbonate hardness and low non-carbonate hardness. The water softening process produces a lot of carbonic acid, which is removed from the water through intensive aeration. Water thus treated has a low pH, and should be hardened with tap water until it has a more neutral pH.
Deonizer- A device for filtering water that uses several ion exchange resins to purify and remove impurities from the water. Deionized water is often used in aquariums to lower the hardness and/or pH.
Crushed Coral- Coral rock that has been finely crushed and is used as a substrate in an aquarium. It is usually used in saltwater aquariums, but can be used in freshwater aquariums when trying to maintain alkalinity.
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