You can also get hang on overflow boxes that you can put the skimmer on (not the typical syphon based units for running a sump) They have 2 chambers, pickup and return. You run your skimmer to draw water from the pickup chamber (has the notches cut in the top) then you have the return go into the other chamber. The benefit you ask? One is more efficient skimming but the main benefit is that you put a sponge in the return chamber and that will catch the micro bubbles. May not get all but it will make a huge difference. This was what I did with my hang on skimmer and it helped a lot.