So I have 2x Fluval U4 filters on the side of my tank, pushing the flow across horizontally, and then down the other side and across the substrate, but the plants along the back of the glass are bending and it don't look right.
Here is a terrible diagram of how that looks.

I had one filter using its bottom outlet (closest to back glass & diffuser) to provide bottom flow and co2 distribution. The other filter in the centre using its top outlet for surface agitation and to also push the flow down the far side. My filters are not quite centred either. so both output nozzles were aiming towards the back glass. This would push the CO2 bubbles from the diffuser along the back, and also all my tall back plants at the back were nearly bending over, like a tree in a hurricane.
Today I tried this approach as my CO2 just seemed to rise up to quick, and I noticed people on here sticking there diffusers at the opposite end.

I also changed the other filter to the top output as-well. The flow coming down the glass now pushes the CO2 down and across the substrate, and the back plants are now not bending, but there not swaying much either, just real slow and gentle, But the water flow is still moving around all of the tank.
Its to early to say if I've improved my flow/distribution, from what I can see more co2 is dissolving, plants are swaying much less, but water is moving around all plants. So not sure how I know what good flow really is, as some plants are nearly idle, but like I say water is flowing past at a fair speed just not forcefully.
A 3rd option I thought might work, was to position both filters either side on the back glass instead, so kind of like how people position there spray bars only my filters can't stretch across like a spray bar.

I could try to aim both output nozzles to the middle of the front glass and hopefully the force would then push the water down and across the substrate in the same way a spray bar would.
Also to mention I am not very good at DIY, just like I'm not good at diagrams, so making a spray bar to attach to either outputs will be quite hard for me, and it may also make the tank look more messy. It would also be challenging as the output nozzles are strange shaped and quite small. Here is a picture: so to be honest I would rather keep it pipe/clutter free as I already have to look at 2 internal filters.

Maybe someone could let me know what they think would work best, or how they would position them if it were your tank? and more importantly the placement of the diffuser. The way I have set it now seems to be good, but like I say not all the plants swaying like they were when I had one filter on bottom output, but the bottom output seemed to strong for the back plants.
Here is a terrible diagram of how that looks.

I had one filter using its bottom outlet (closest to back glass & diffuser) to provide bottom flow and co2 distribution. The other filter in the centre using its top outlet for surface agitation and to also push the flow down the far side. My filters are not quite centred either. so both output nozzles were aiming towards the back glass. This would push the CO2 bubbles from the diffuser along the back, and also all my tall back plants at the back were nearly bending over, like a tree in a hurricane.
Today I tried this approach as my CO2 just seemed to rise up to quick, and I noticed people on here sticking there diffusers at the opposite end.

I also changed the other filter to the top output as-well. The flow coming down the glass now pushes the CO2 down and across the substrate, and the back plants are now not bending, but there not swaying much either, just real slow and gentle, But the water flow is still moving around all of the tank.
Its to early to say if I've improved my flow/distribution, from what I can see more co2 is dissolving, plants are swaying much less, but water is moving around all plants. So not sure how I know what good flow really is, as some plants are nearly idle, but like I say water is flowing past at a fair speed just not forcefully.
A 3rd option I thought might work, was to position both filters either side on the back glass instead, so kind of like how people position there spray bars only my filters can't stretch across like a spray bar.

I could try to aim both output nozzles to the middle of the front glass and hopefully the force would then push the water down and across the substrate in the same way a spray bar would.
Also to mention I am not very good at DIY, just like I'm not good at diagrams, so making a spray bar to attach to either outputs will be quite hard for me, and it may also make the tank look more messy. It would also be challenging as the output nozzles are strange shaped and quite small. Here is a picture: so to be honest I would rather keep it pipe/clutter free as I already have to look at 2 internal filters.

Maybe someone could let me know what they think would work best, or how they would position them if it were your tank? and more importantly the placement of the diffuser. The way I have set it now seems to be good, but like I say not all the plants swaying like they were when I had one filter on bottom output, but the bottom output seemed to strong for the back plants.
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