It is there for a reason. Like stated above, this is one if the reasons we have sumps. Mine is plagued with nuisance algae growth, but it keeps it out if my display. Because of that, I would not increase the flow unless you try growing algae in there. The cyano is consuming the crap out of your water and I'd want to keep it like that. Either remove it and chance it showing up in the display or have it return or address the issue with the usual ways to nix cyano, improve water quality.
So, reduce feedings. I only feed my tank twice a week.
Keep feeding to a minimum, only what your fish will consume in a short time frame.
Use ro/di water to ensure your problems are also coming from your water supply. If not an option, atleast use distilled water, just buy it for 88 cents a gallon at walmart it wherever.