I've always been told that anything short of sloshing over the top is too little flow

more flow is better...
you need some random currents in there,a constant flow in 1 direction isn't good for the coral...
if you're on a tight budget like a lot of us,try to add a couple of MaxiJet 1200 with the SureFlow upgrade kits(1 on each end)mount 'em low and aim em upward toward the surface so as to not be blowing water onto any coral,the under tow of water is awesome....that'll produce about 2100GPH per power head and should be enough flow for your tank,you could also use the maxijet 900 with the sureflow kits and get about 1800gph per power head...
I have 4 MJ 1200's,2 on each end of my 360g(8 feet long tank)and they're on a natural wave wave maker(2 on/2 off)cycling every 3 minutes,the under tow in my tank is amazing.....
the problem with using these pumps on a wave maker is when they first start up,sometimes they want to run in reverse and it makes a rattling noise until it take off in the correct direction,I've found that if you'll let them run for a week or so constantly on and allow the bacterial film to build up on 'em that you can usually plug 'em into the wave maker and they work great,or at least mine are....
as you probable know,maxijet power heads are probable the most dependable pumps on the market