120 gallon. Eheim 2217 fluval fx6 and 106 and 2 medium sponge filters. Only have 2 fish in there, 1 8 inch red dragon fh and a 4 inch kamfa. Recently updated my filtration, used to do 20-30% weekly. Light fish load, but messy fish. Don't feed much other than pellets. Should I keep up with the same schedule, or is it not necessary. Also I gravel vac every time I do a water change. Thanks guys!