Is it possible to do a 95% water change without re-cycling? I have two established filters (4 months) running plus whatever bacteria are in the gravel. My tank is a 29g., it will hold 4 med. size fish when complete. I also have about a 10g. treatment of bio-spira.
mixing substrate in an established aquarium
- Thread starter blue demasoni
- Start date
You just want to add new substrate and not remove any of the old?
Most of bacteria is in the substrate and filter media, not the water. So, you can do a 95% water change without any problems.
Most of bacteria is in the substrate and filter media, not the water. So, you can do a 95% water change without any problems.
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I recently tore my goldifish tank completely apart and scrubbed everything down rinsing the substrate in tapwater and even lifted the empty tank off the stand to wash it really well. My goldfish lived in a plastic bucket during the couple hours this clean took with their filter attached to the bucket. After I was done, I refilled the tank, waited for it to stabilize and re-added the fish. My ammonia and nitrites both remained at 0.0 since the bacteria in my biowheel did not get removed during this extreme cleaning of the tank.