Well first, I would like to point out that with two t5HO bulbs, you're running high light on that tank. High output bulbs really do put out more light than a lot of people think, and excessive light is very often a contributing factor to algae. Considering that none of the plants you mentioned require that much light, you might want to think about only running one bulb.
As for flow, it has been my experience that increasing it and eliminating dead spots does help control algae, though not so much to get rid of it. You could get a powerhead like a koralia or something to increase flow without purchasing a new filter, if you'd like to go that route. I see you've got a gourami in there, though, and they don't really like a ton of flow. Just something to consider.
What exactly does your dosing and water change schedule look like, to get a better idea of everything?