FAQ: Will seed kill off my existing bacteria colonies?

No.  seed does not attack or kill your existing bacteria colonies, nor does it "starve out" your existing bacteria colonies. seed does not cause ammonia spikes, and can be added to completely established aquariums with no risk to the fish. The beneficial bacteria in seed is much better at surviving adverse conditions than most strains of beneficial bacteria found in aquariums, which means that aquariums which are supplemented with seed will typically have a much larger population of the type of bacteria in seed than other types of beneficial bacteria.  This is not because seed is harming the existing bacteria colonies in any way - it is simply better at surviving and stabilizing your tank.