OK I know this isn't the best of skimmer but its all I have right now. About 4 days ago on its own the skimmer stopped pulling anything out at all. The foam is very thin and just like water. I took it off the tank and cleaned it and changed the airline tubing out for new. Does anyone know what has happened and how to fix this? I am worried b/c I am pratically going skimmerless, it doing nothing.