So this came with a good amount of attachable spray bar attachments. Would you just put them all together and put it on the back wall? I know the bigger the bar the lower the flow strength but still the high turnover. Flow would just be back to front instead of side to sideI would normally disburse the outflow from the filter more than turning it down.. if you have an area where flow is lower the chances is the fish will work up to swimming more in the open water.
For CO2, I would personally use an inline reactor as it will give the best dissolved gas... Making sure that it is disbursed through the tank is another matter which should probably be enough anyway.
Appreciate the help. So my co2 tank is on the opposite side of the tank from the filter. I can lengthen the hose from the co2 tank to the diffuser to get the diffuser on the other side. Not enough room to move the filter.yes, the longer the spraybar, the les currrent in the aquarium. If feeling handy, you can always split the return hose and have multiple spraybars (or jets) its all a matter of opinion and preference.
if using a diffuser, I would likely position it as low down as possible, positiin it as close as possible to below the first hole from the spraybar (closest to the filer) assuming just one of them, and finally I would have the spraybar pointing maybe 30 degrees downwards to force the CO2 bubbles to stay in the water longer.