totals
- Thread starter 72gallon
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robchuck
Active Member
A good rule to start with is 1" of fish per every 5 gallons of water. If your tank is able to support a bioload of that size, you could try pushing it with another fish or two; making sure that the addtional fish aren't stressing the bioload too much.
As Sabby mentioned, the rule is partially based on the behavior of the individual fish. For example, 10 - 1" gobies would be less stressful to your bioload than 1 - 10" lionfish. If you're looking for a larger quantity of fish, it's much easier to add several smaller fish, than only a few larger fish.
Also, the shape of your tank effects the rule as well. Swimming space and surface area are also key components for determining the amount of fish you can keep. Take a tank with a 48"x18" footprint for example. A 75 gallon tank uses this footprint and is only 21" high, while a 110 uses this footprint as well and is 30" high. Both tanks have the same footprint for swimming area for the fish (most fish swim horizontally and don't care much about the height of a tank) and also have the same amount of surface area for gas exchange. The advantage of the 110 is that it has more water volume to dilute pollutants.
As Sabby mentioned, the rule is partially based on the behavior of the individual fish. For example, 10 - 1" gobies would be less stressful to your bioload than 1 - 10" lionfish. If you're looking for a larger quantity of fish, it's much easier to add several smaller fish, than only a few larger fish.
Also, the shape of your tank effects the rule as well. Swimming space and surface area are also key components for determining the amount of fish you can keep. Take a tank with a 48"x18" footprint for example. A 75 gallon tank uses this footprint and is only 21" high, while a 110 uses this footprint as well and is 30" high. Both tanks have the same footprint for swimming area for the fish (most fish swim horizontally and don't care much about the height of a tank) and also have the same amount of surface area for gas exchange. The advantage of the 110 is that it has more water volume to dilute pollutants.