hi I have a very old aquaclear 150 on a 25gallon tank with angel hair and carbon. I was told that i definitely needed a filter upgrade but does that mean I should just get a brand new filter, or to add something else to what i already have?
I'm cycling the tank so i have no fish yet
and also people around here seem very concerned with the gph
-is there a rule for how many gph
filtration is needed for a 25gal tank?