I currently have a 37 gallon tank with an Aquaclear 70. I am considering adding a canister filter. reason is back up filtration (had motor die on Aquaclear and had to replace which left tank un filtered for a few days) and I want to add a UV sterilizer and figured it would be best on the outlet of a canister filter. I am considering either an Eheim 2215 or 2217. question is can I have too much water circulation with the 2217 and the AC 70 running at the same time for the fish with this size tank?