I have a 100 gallon freshwater aquarium with two angels, large goldfish, a koi and a pleco. My angels have been under some distress the past couple of days due my recent tank upgrade two weeks ago. I did a water change last night and the fish seem to be more comfortable at the top of the water as if they are not getting enough oxygen. I currently have a Rena Xp2 filter canister system and a 60" bubble wand across the bottom but it doesn't seem to be enough. I am looking into purchasing a wavemaker for increasing the water circulation & wanted to know if anyone has had luck with one, which kind & what size I should get for a 100 gallon.