Hello I am having trouble with my skimmer. I bought a skimmer from someone off craigslist and I tested it to see if it works and all it seems to do is circulate the water through the skimmer and out the return line. I am new to the hobby, but Im pretty sure I should see some bubbles and foaming on the top of the water. The pump has an air line on it, and I make sure that it is out of the water, and still nothing. Any ideas?
Also, I dont know what type of skimmer this is, there are no markings. here is a pic. Please help!
http://reefcentral.com/gallery/data/500/191781myskimmer.JPG
Also, I dont know what type of skimmer this is, there are no markings. here is a pic. Please help!
http://reefcentral.com/gallery/data/500/191781myskimmer.JPG