I don't know if you have seen these Ray but there like sea swirls or the mocean thing by vertex for 20 US bucks
there are two sizes 1/2 inch and 3/4 inch 1inch
I would pick up a couple for my tank if you can get em,.
http://www.aquaticlife.com/pumps/flo...g-wavemakers#1
I would want the 1inch diffuser part Item
#660368 from there wed site