I have a eheim canister filter with the outlet right over my heater. I also have a aquaclear 70 over-the-back filter.Is this your only source of water movement, or are there filters too? What fish do you have?
I keep reading posts from folks that complain about too much flow from Koralias, so "obviously not enough flow" is new to me. I guess it depends a bit how "enough flow" is defined, where the pump is placed, etc. Also some fish don't like a lot of flow, others do.