Biological Media During Fishless Cycle

jweiner

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I’ve read mixed things about this issue. During a fishless cycle, is it best to leave the biological filtration (Matrix in my case) in the sump or remove it during the process? Thanks in advance.
 

Dan_P

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I’ve read mixed things about this issue. During a fishless cycle, is it best to leave the biological filtration (Matrix in my case) in the sump or remove it during the process? Thanks in advance.
It probably does not matter.

The nitrifying bacteria are going settle every where in the system and proliferate where the environment suits them. I would proceed with the matrix installed if that is your preference
 

Randy Holmes-Farley

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Some folks have stated that it is preferable to have the bacteria inhabit the tank only during a fishless cycle.

I don't see a rationale for that thought.
 

Fish Fan

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Some folks have stated that it is preferable to have the bacteria inhabit the tank only during a fishless cycle.
People say this about mechanical media like floss and sponges, etc. When you add bottled bacteria to a new tank, you want the bacteria to settle and grow on the rocks and sand. Many feel that it's counterproductive to have the mechanical filter media catch any of the bacteria that have just been added, only to then be removed. For that reason, some don't use mechanical media during the cycle, but bio media you absolutely want to be populated by the bacteria you're adding 🙂
 

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