Diy Fish Tank Bio Filter

how do we start the beneficial bacteria growing?

i just finished making my own DIY sump filter. ive added alot of bio filter media. how do i start the beneficial bacteria growing? do i just have to wait? if i do how long do i have to wait? or do i need to get/buy some from the local aquarium store? my fish tank is highly polluted with ammonia and fish waste right now.
thanks guys!
looking foward to seeing your answers [=

The bacteria will just start growing on its own. You will have to wait at least a few day for the levels to go down. water conditioner will help bring the levels down.

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