ok when i bought my 210gal tank it was used and came pretty much with everything including the protein skimmer which is an REEF OCTOPUS 3000 and when i tried testing it to see if it worked well i realized that the pumps does lift the water all the way to the top but with very minimal bubbles, there is a small hose that is connected to the inlet of the pump and that is out of the water... so i figured well maybe the pump isn't any good so i ordered the same model of pump and same problem....what could be happening there are little bit of bubbles but not to were i could say okay my skimmer is working..... any suggestions as to what could be going on