in my 75 gallon tank i have 2 402 power heads and a fluval 404 pushing the water around in the tank. someone had mentioned to me that the more current the better but i just can't seem to keep the sand from blowing into dunes and into the live rock. can someone please advise me as to how much current or suggestions. i know i have too much sand in there now. i think i need to remove about 20-30 pounds of it. will i mess up the cycle in there if i start scooping away at the sand? the tank is very new, i have life on some of the rock... sponges, feather dusters, zoos, some muscles or clams wedged in the rock, starfish...