The rule is 1 for each 10 gallon according to what I read. I do have two in a 10 gallon for now.
I don't think the gallons matters as much as the BASE dimension. Vertical wise, i don't think it really matters as long it is about 12-24 inches high. I think the base dimension is what matters more.
You sound like a teenager and that is why you don't have the funds for them. If this is true, see if your parents can help out.
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I will be back!


