Help My Flow - 155g Bowfront
I have a six-foot long bowfront tank and I'm looking for the best option for flow - I have two Rena XP3 with vertical spraybars and two Koralia pumps. I run pressurized CO2 through reactors on both filter returns.
It appears the consensus for well-planted tanks is a horizontal spraybar on the back and pointing to the front glass - I've been reluctant to do that because I have a huge wedge of driftwood with large java fern that's reaching the surface, which would block some of the flow. Plus I'm not crazy about spending the time and money for custom spraybars. I also like some plants getting tall enough to lay on the surface, and don't want them blown all around.
So, I've experimented with a few setups:
1. Both filter intakes lower left; One return next to it pointing right; second return in middle pointing right with lower elbow pointing to front right corner; Koralia in top front right pushing water R-L across front. Second Koralia top left pushing water L-R in same direction as filter outputs. After trying methods #2 and #3 below I think this was the best.
2. Both filter intakes lower middle. Intent was two half-tank circulating currents. Filter returns at back left and back right - spray bar pointing toward intakes so CO2 hits the tall background plants; lower elbows pointing toward front middle to push CO2 to foreground plants. Koralias at front top right and left, pointing to middle. Seems like one side's flow is stronger than other and these currents "fight" each other and don't work as envisioned.
3. Both intakes lower middle. Same spraybar/elbow orientation. Koralias on back of tank, one top back right and one top middle, and they point toward front glass at slight diagonal to get a rolling effect as they push water to the front glass. Appears to have decent flow, but I'm seeing GDA and diatoms for first time in a while, so something tells me this is less than optimal.
The wedge of driftwood at center-right is a problem, I know, but it's a nice focal point and too dense to saw into two pieces. Any other recommendations for a flow pattern with two filter returns and two pumps?