I have never had trouble with my tubes getting clogged except when dosing kalk. When the tubes would get clogged from the kalk, I would put both ends in a diluted muriatic acid bath and turn the pump on. After a few minutes the acid cleans out the entire tube. I then run a tiny bit of the kalk water through the tube and into another bucket which will counteract the small amount of acid left in the tube. It's then good to go for another month.