some are like this, but not all... you ended up creating a large scale biological fiter that rendered the tank filter obsolete other than to eutrophize the fish

some are like this, but not all... you ended up creating a large scale biological fiter that rendered the tank filter obsolete other than to eutrophize the fish tank environment[good] the basic play is to balance the system of give and take between plants as a nitrogen sink, and a biological nitrogen source... the cycle of nitrosomas and nitrobacter conversion of ammoniacal substance to nitrite and nitrate available for plant assimilation occurs in the particulate accumulated in the gravel bed... fish are convienient and tasty but very often a compost tailings lagoon is used...there is a wide acceptance of bio remediation of sewage, hor farm runoff in the niagara escarpment area...