Posted: Sat Jan 23, 2016 9:54 pm Re: Fluval fx6 res tank
Roughly every two months here. Not quite as bad as yours, but I should do it monthly.
I don't use any of the blue pads in mine. Just media.
Tobi a RES born in 2012
1 dog, 1 teenager, 3 aquariums filled with fish, snails, shrimp and a bit of algae