I have a new 55gal cichlid tank, I am presently using gravel and river stones. Filtration is power filter and underground with 2 power head. I am worried about changing to sand to keep ph because of power heads. I am also considering adding more river stones later right now things are going well since my fish are small. I am also not entirely sure which cichlids I have only that they are Lake Malawai african.
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