The Inch per Gallon "Rule"

by fballguy

The inch per gallon rule does not work for any aquarium. And here is why:


It does not account for waste produced by fish. Every fish is different. According to the inch per gallon "rule", a 3 inch betta produces the same amount of waste as a 3 inch oscar. Wrong. Oscars have a wide body, and bettas have a narrower body. Therefore, the oscar has more body mass, and produces more waste, taking up more bio load. Another example also includes the oscar. A 10 inch oscar produces 100 times the amount of waste as a 1 inch oscar. Can you imagine 100 one inch oscars in a 10 gallon tank?


It does not give any information about compatibility. According to this "rule," it is safe to put 3 male bettas in a 10 gallon tank. Obviously this is false. Using the inch per gallon "rule," anything can go together as long as you do not have more inches of fish than gallons of water. So apparantly pirhanas and guppies, tiger barbs and angelfish, rainbow sharks, and discus, all will make great pairs. Wrong. The "rule" says nothing about the compatibility of different fish.


It does not tell you that coldwater fish and tropical fish do not mix. According to the inch per gallon "rule," goldfish and bettas go great together. Wrong. Bettas need tropical temps between 78 and 84 degrees to be at their healthiest. Goldfish need temps below 72.


It does not give any information about water requirements. According to this "rule," South American cichlids and African cichlids will go together just fine. Wrong. South American cichlids come from the very soft, acidic waters of South America. African cichlids come from the very hard, alkaline, African Rift Lakes. Putting these fish together is going to end in certain death.


There are many so-called "rules" for aquarium stocking. But they all have flaws. The only real rule you can follow is to do your own research. Libraries and the internet are full of great information. Look up fish you want to get, before you get them. Make sure the fish you want to get are ones that 1)Will fit in your tank, and 2) are compatible with the other fish you have or want. That way you avoid getting yourself into a fish problem that you can't get out of.



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