Good advice so far - just to summarize:
- Try to place it on a "pedestal" rock, close to the surface - it will get more light there.
- Even though the water flow could be more, it should be OK if it is "chaotic" - have the power heads directed towards each other, to create eddies and irregular water movement. DON'T aim a power head directly at the anemone, though...
- Once it has settled, try to vary what you feed it. A more natural diet would be pieces of fresh fish and pieces of shrimps or prawns (with shell, intestines, etc.)
- Make sure that it "smokes" (expels the remains of the previous meal...) before you feed it again - every 3-4 days should be OK.