Cycling a New Tank and Fish Choice:
A tank can be cycled using fish (actually their wastes, other aquatic animals work as well) or ammonia added directly. Cycling a tank with fish means adding fish so that they produce ammonia to promote the growth of the bacteria that convert it to nitrite and then nitrate. A tank is "cycled" when ammonia and nitrite readings are sustainably zero (they stay zero for at least a few weeks), and nitrate readings increase. Many people tell new aquarists to cycle their tanks with cheap or trash fish like feeder fish, danios, guppies, etc., and then to get rid of them or return them to the store. I do not believe this to be a good choice. First, these fish are not respected and being treated poorly are most likely full of diseases, bacteria, and/or parasites. These are then introduced into the new tank and stay there. Second, after the tank is cycled, the fish have to go somewhere. If unwanted fish were used, they either go back to the store (in which case the stress most likely kills them) or are killed outright. It is much better to use fish that one intends to keep to cycle the tank. There is NO reason that a single initially-healthy fish should die during cycling (see information above on water changes). Anyone who tells you that it is "normal" for a fish to die is misinformed or trying to sell you more fish.
The fish desired in the tank should be determined ahead of time. A few of the most hardy of those should be the first inhabitants of the tank that will get the nitrogen cycle going. These fish will remain in the tank when the tank is cycled, and new fish are added. Good cycling fish that can be kept in most community tanks include fancy guppies, small danios, small tetras, small barbs, white cloud mountain minnows, etc. Even most so-called sensitive fish can be used to cycle a tank without dying. In rare cases, it may actually be necessary to cycle a tank with fish that cannot remain in the tank forever (like a piranha tank). Ideally, these fish would be moved to a tank of their own after cycling. Algae eating and bottom dwelling fish such as plecostomus, otocinclus, algae eaters, snails, corydoras catfish (cories), and freshwater shrimp should not be added until after the tank has been set up for a while and algae and bottom debris are present.
by Robyn's Water Chemistry Page
http
/www.fishpondinfo.com/chem.htm#cycle
A tank can be cycled using fish (actually their wastes, other aquatic animals work as well) or ammonia added directly. Cycling a tank with fish means adding fish so that they produce ammonia to promote the growth of the bacteria that convert it to nitrite and then nitrate. A tank is "cycled" when ammonia and nitrite readings are sustainably zero (they stay zero for at least a few weeks), and nitrate readings increase. Many people tell new aquarists to cycle their tanks with cheap or trash fish like feeder fish, danios, guppies, etc., and then to get rid of them or return them to the store. I do not believe this to be a good choice. First, these fish are not respected and being treated poorly are most likely full of diseases, bacteria, and/or parasites. These are then introduced into the new tank and stay there. Second, after the tank is cycled, the fish have to go somewhere. If unwanted fish were used, they either go back to the store (in which case the stress most likely kills them) or are killed outright. It is much better to use fish that one intends to keep to cycle the tank. There is NO reason that a single initially-healthy fish should die during cycling (see information above on water changes). Anyone who tells you that it is "normal" for a fish to die is misinformed or trying to sell you more fish.
The fish desired in the tank should be determined ahead of time. A few of the most hardy of those should be the first inhabitants of the tank that will get the nitrogen cycle going. These fish will remain in the tank when the tank is cycled, and new fish are added. Good cycling fish that can be kept in most community tanks include fancy guppies, small danios, small tetras, small barbs, white cloud mountain minnows, etc. Even most so-called sensitive fish can be used to cycle a tank without dying. In rare cases, it may actually be necessary to cycle a tank with fish that cannot remain in the tank forever (like a piranha tank). Ideally, these fish would be moved to a tank of their own after cycling. Algae eating and bottom dwelling fish such as plecostomus, otocinclus, algae eaters, snails, corydoras catfish (cories), and freshwater shrimp should not be added until after the tank has been set up for a while and algae and bottom debris are present.
by Robyn's Water Chemistry Page
http
/www.fishpondinfo.com/chem.htm#cycle
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