Sorry, was a bit confused about the use of the Koralia pump. I took it that the entire reason for the pump was to just break up the bubbles coming from the sponge filter.
I'm just wondering, what is your reasoning for increasing circulation over increasing filtration?
I run a sponge filter and a Rena XP2 canister in a 40b and it is almost too much circulation in that tank. I have another 44 hex tall tank that I keep angles in and I have to turn down the penn plax 700 canister output to not blow out the angels with too much circulation and I run a sponge as well on that tank to increase filtration as I do not feel that I am getting enough water exchange with the restricted flow I have set up on that tank.
I personally, could not see adding more circulation but do like having the extra filtration on the cheap.