Has anyone had problems with knots forming in the tubes on their canister filter? If so, how do you deal with this problem? I've had my Reyna for three months and it was running fine at the last filter change a couple of weeks ago. Tonight I laid down on my couch and noticed there was no water circulation on the surface above the outlet tube. I checked it and found a knot where the inlet tube hooks into the canister. I moved things around and after a lot of frustration finally got it flowing again. I'm worried though about another knot forming. It frustrates me that something like that can even happen with such an expensive machine.