Swapping filters between two tanks?
I have two well established tanks right now. One is a 20L community tank while the other is a 10 gallon that only has a male betta. I figured out recently that I am wasting filtration capacity with each of my filters. The community has a filter good for 10 gallons while the betta has a filter for up to 20! Is it safe for me to trade filters between the two of them? I thought I was playing it safe having a lower capacity filter for the community since it has guppies, but I'm not sure now. I only have these two filters and do not want to spend extra for a third if I don't have to.