Fluval evo overflow problem ? Trickling

[Nanolifeuk]

The surface isn’t being skimmed as it should. So I raised my intank basket. There is now a bigger drop between DT and overflow water levels (where my thumb is in pic. But it’s only trickling. Is this correct/ enough ?

 

[reefpunk707]

I'd start with cleaning the return pump and the stock sponge if you have it. Maybe change the filter floss too if that dosent help. I had that tank and ended up upgrading the return pump.