Oh what a mess to clean.. but wow, it's so worth it. Congrats on getting such a great tank setup.
We don't want canister tubes to loop down like that because muck is going to collect inside at the bottom of those loops. That will restrict the diameter of the passage at those points which limits how much water gets through them into the pump and back into the tank. It also lengthens the upward distance the motor has to push return water before it reaches the top. So that also slows down the flow rate.
I had a question, the Fluvals, or any canister in general. I read that it's bad to have "loops" on the hoses for canisters, and never understood why. I saw that your canisters has these "loops" that dip down, before it goes up. Do you notice any problems while operating?
We don't want canister tubes to loop down like that because muck is going to collect inside at the bottom of those loops. That will restrict the diameter of the passage at those points which limits how much water gets through them into the pump and back into the tank. It also lengthens the upward distance the motor has to push return water before it reaches the top. So that also slows down the flow rate.