[GonnaTryCichlids]

Hello: If I set up a new 125 gallon tank and put the well established filter from my old 25 gallon tank on the new tank...how long before the old filter will be handling the same number of fish as it was in the old tank? In other words, if everything remains the same as far as the filter and fish, have I already taken care of part of the cycling process in the new tank? The fish won't be making any more waste than before, and the filter will have the same potential (or will it?). I can leave the old filter in place for as long as necessary to get the new filter populated. What other factors are there to consider as long as the other water parameters are matched extremely closely (pH, KH, GH...)? Know what I mean? Thanks!! RB :fish:

 

[DJRansome]

The old filter will support the same fish in the new tank, but you will want more circulation. The new filter will grow beneficial bacteria in two weeks. But both filters will still only support the original number of fish. To increase the beneficial bacteria you will have to add fish gradually and let the beneficial bacteria catch up between additions.

 

[GonnaTryCichlids]

Thanks DJRansome! I will have the circulation from the old filter (a Marineland Eclipse) and the new Eheim Classic 600 canister spraybar. Do you think I should throw in an airstone temporarily? opcorn:

 

[fmueller]

An airstone can't hurt, but I don't think you need it.