how many gph of filtration should i have for a 55 gallon aquarium? i was thinking 550 gph so the tank is filtered 10 times in an hour. i got 200 gph on my 20 gallon but im thinking about adding another 100-150 gph if the tank isnt clean when i add more fish. the 55 gallon will be housing african cichlids or some texas cichlids with some texas holy rock. 
