Converting to bare bottom...problem with a long tentacle anemone?

I have one and he does prefer the sand. He was in a rock crevice for awhile, but after he found his spot on the sandbed, he has never been back in the rocks.........could you just have less of a sandbed, say a couple inches instead of no sand at all?

 

I think you would be surprised. On my 150 I had almost 6k GPH with a sugar fine sand bed and didn't have any issues. Not saying don't go BB, but I would toss the powerheads in and give it a shot. If you start to see sand blowing around, then take them out and think about removing the sand.
I have a theory about people that have issues with powerheads. It may be wrong, but I will give it anyway, so here goes...
IMO 2k gph from a SINGLE powerhead is no the same as 2k GPH from multiple powerheads (ie four 500 gph powerheads) simply because in the first scenario you are getting a single concentrated blast of water flow versus dividing it by four much calmer blasts in scenario two. I think many people try to minimize their number of powerheads (understandable, who really wants to look at those instead of awesome corals and fish) but end up getting 1-2 really beefy powerheads for their tank rather than tuning them back a bit and maybe adding an extra one.
Just my opinion, but my methods have worked very well for me!

 

Another thing to consider is your rockwork. Very little rockwork will allow for much more sand movement than more rockwork would.