try running some filter floss in you current somewhere, its probably fine sand suspended in the water. check ammonia and nitrite levels to rule that out also. if you have an extra powerhead around, you can take a tupperware container and put a hole in the lid big enough for the intake on the pump. put some holes or cracks in the side of the container to let water in and fill it with filter floss - the kind that looks like cotton. put the whole contraption in the water and change the floss every 2 - 4 hours. may not look pretty, but it should clear up the water.