My son's 14 gallon biocube has been up and running for 3 months. the problem we are having is with the filter system. it seems to re-circulate sand particles over and over. The water never has cleared since the initial set up. The store where we bought it has sent a tech out twice with no definitive solution. Has anyone ever experienced anything like this? They want us to bring it back to their store so they can monitoe it daily to see what the problem is. I'm afraid it will stress the fish and corals to much. Your Thoughts... Thanks