a note on sand storms-- I have a CL with a seq. Dart on a OM 4-way and the outlets are small jacuzzi jet ports. When I first turned them on, the size of the nozzles focused the flow and it created quite a force within the tank; I had that same sand storm. I should have installed the large ports instead. But the answer wasn't to cut back on flow as much as force and I did this by removing the ball directional (nozzle) part of the jacuzzi bulkhead. I kept the flow, but spread it out; more like a natural surge. Since then my sand has aquired algae and critters and stuff to bind it together and I don't worry about sand storms. So, don't forgo a sand bed just because of water movement, there are a number of remedies to that issue. Sand's worth the effort asthetically as well as for the health of any inverts you might want. IMHO