Index Of (jpg) Cancun How Much Filtration Is Needed For A 20-30gl Fresh-water Fish Tank? And Do I NEED A Water Heater?

How much filtration is needed for a 20-30gl fresh-water fish tank? and do i NEED a water heater? - index of (jpg) cancun

I took the plastic tube and insert the air hose in a shell, this work will die eventualy fish? Do you really need heating and at the top?

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