Oh, that sparked my memory lol. I run a CPR overflow with an aqualifter pump. This will prevent losing the siphon. It works great. The CPR I have is the smallest they offer as I had it on my 36 gal
prior to the 55. As for a return pump I am using a mag 5. It comes with a silencer, which is really a sponge that pops onto it. There isn't a need for it, the pump runs silently. Along with that, it was preventing my pods
from getting into my display tank.