I agree, Cichlids produce a growth inhibitor hormone.
That builds up in the water. So even if your water quality is good,
The hormone builds up. And the only way to remove this, Is water changes.
The smaller the tank, The more often the water changes are needed.
Spike
Btw, some people actually take advantage of this to purposefully stunt their cichlids so that they can be kept in smaller tanks. ;D
