eco23
Aquarium Advice Addict
jetajockey said:Because it has the potential to give you false readings for one. The type of bacteria they use in powdered supplements especially is not the same kind that is naturally responsible for the nitrification process in an aquarium. It does the job, but very poorly by comparison, and does not sustain itself. With that in mind, it can possibly give you the idea that all is well in the tank, when it really isn't, and when it dies off you may have a toxin spike because of it.
There's also conjecture that it competes with the proper nitrifiers for a food source.
Perfectly summed up.