Lately, I've been seeing a few people using the inch/gallon rule when it comes to stocking fish. This "rule" is a myth. I don't know how it came about, but this "rule" is no where near acurate when it comes to stocking a real life aquarium.
Think of it this way... if the inch/gallon rule was true... then I would be able to stock 6 fully grown convict cichlids in a 30 gallon tank, and they should all be happy. Is this true? Not even close. In reality, putting only two fully grown convicts in a 30 gallon tank would be pushing the tank's limits.
Why do you ask? There are a few things to consider when stocking a tank:
1.) Fish behaviour. Not just their everyday behaviour either. You need to consider how the fish acts when it eats. How it acts if it breeds. How it reacts to its environment (ie. planted tank vs. non-plant tank). You also need to consider how the fish will react to other fish you might be into the tank (ie. putting fish that nip fins with fish that have long fins). Whether the fish is an active swimmer or not also comes into play.
2.) Fish diet. Fish don't all eat the same things. Some fish require higher amounts of protein in their diet, while others cannot have much protein at all. The list goes on, but you need to insure that either you can feed the individual species of fish correctly, or that the diet of all the fish in the tank are compatible.
3.) Fish size. Yes, fish size is important as the inch/gallon rule suggests. However, what the inch/gallon forgets to mention is that fish are 3 dimensional creatures. There are more to fish than just their length. One inch of neon tetras cannot be compared to once inch of a convict cichlid.
4.) You also need to put into consideration what kind of filtration you have running. Generally, tanks with a higher stock of fish will have more filtration, compared to one with less fish.
5.) Tank shape. You also need to consider the surface area of your tank. Generally, its better to have a longer and wider tank, compared to a deeper tank.
There are many variables when it comes to deciding what to stock your tank with. Clearly, the inch/gallon rule is flawed in more than one way. The only way to really know whether or not your planned stocking will work is to do some work yourself. Research like crazy, and afterwards, ask questions.
-Richer
Think of it this way... if the inch/gallon rule was true... then I would be able to stock 6 fully grown convict cichlids in a 30 gallon tank, and they should all be happy. Is this true? Not even close. In reality, putting only two fully grown convicts in a 30 gallon tank would be pushing the tank's limits.
Why do you ask? There are a few things to consider when stocking a tank:
1.) Fish behaviour. Not just their everyday behaviour either. You need to consider how the fish acts when it eats. How it acts if it breeds. How it reacts to its environment (ie. planted tank vs. non-plant tank). You also need to consider how the fish will react to other fish you might be into the tank (ie. putting fish that nip fins with fish that have long fins). Whether the fish is an active swimmer or not also comes into play.
2.) Fish diet. Fish don't all eat the same things. Some fish require higher amounts of protein in their diet, while others cannot have much protein at all. The list goes on, but you need to insure that either you can feed the individual species of fish correctly, or that the diet of all the fish in the tank are compatible.
3.) Fish size. Yes, fish size is important as the inch/gallon rule suggests. However, what the inch/gallon forgets to mention is that fish are 3 dimensional creatures. There are more to fish than just their length. One inch of neon tetras cannot be compared to once inch of a convict cichlid.
4.) You also need to put into consideration what kind of filtration you have running. Generally, tanks with a higher stock of fish will have more filtration, compared to one with less fish.
5.) Tank shape. You also need to consider the surface area of your tank. Generally, its better to have a longer and wider tank, compared to a deeper tank.
There are many variables when it comes to deciding what to stock your tank with. Clearly, the inch/gallon rule is flawed in more than one way. The only way to really know whether or not your planned stocking will work is to do some work yourself. Research like crazy, and afterwards, ask questions.
-Richer
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