Just want to see what your guys opinions with WC. I have tank 10X3X2.5 (L/W/H) with breeding Paired Motoro, 1 x large peacock bass and 2 x silver dollar. Filter: sump 6x2x18" with 25 ltrs of K1, 4 ltrs of matrix, 5 ltrs marine pure. Would your guy thing I can get away with 50% water change in every two weeks?? at the moment I do 25% WC weekly. I feed the fish once a day (mainly Hikari Sinking Cani) then market prawns once a week.