Hey guys, I was wondering how often can you scrub your bio film partially in a 125g? I have a heavy bio load. I have 3 oscars (two 7 inch and one 6 inch) as well as a 3 inch jack dempsey, a 5-6 inch pleco, two 3 inch bala sharks, 2 angelfish, 3 small danios and a black skirt tetra. Last thing i wanna do is disrupt the nitrogen cycle. Any help would be greatly appreciated, thank you.