My 180 has been up for almost 2 years and I have decided to start placing corals. All I had to begin with was a pair of maxi jet pro 1200s set up as circulation pumps (1300gph) each. One on each side near the top. I also have a 1200gph return. I was told that was not enough for my tank if I wanted to do corals. I was directed to buy a hydor wave maker and 4 koralia evolution 1500s. I put two on each side and run them on the alternating wave mode. so 5 seconds left on right off then 5 seconds right on left off. I've played with the timing and no matter what it blows my sand everywhere. Is this TOO much flow? I've seen many other tank with probably twice the flow in a smaller set up without issues. It's basically taking all the sand from the middle of my tank and pushing it to the sides. Would putting two on the back help? I think the flow down the glass will do the same and don't want to keep stressing my fish.