Hey bought a new filter 3 weeks ago and have been running it along with the old one.
How long will it be until the new one is cycled?? and I can take the old one out?
I normally use 4 weeks if I need to make it quick (display tank), or 6 weeks if I don't (fish room, back when I had one). If you are able to move the media from the old filter into the new one, then instant on replacement of media. It is always safer if you can move at least some old media into the new filter. So far this has always worked for me
