Opinions on the Rena XP3 vs a 2nd AC110 on my 75 gal FW. Ready to purchase the 2nd filter so I can start fishless cycle. I know the 2 AC110's are more than adequate, but would the canister be that much of a better choice (it is twice the price of the AC110)?

Later on, I am also considering adding a Hydro V sponge filter (125 gal) to be powered by a SunSun YT-8000 battery powered air pump (runs on constant AC power and kicks in on DC when power goes out), in case of power outages. We don't have many outages, but it would be worth the expense for peace of mind for oxygenation and bio-filtration.

Opinions please.