I am having trouble with my red prizm skimmer, I do not seem to be able to get any water flow to come out, It is used so it may be just not working, I took it apart , and it turns on but does not suck any water, are the blades suppose to spin like a wheel? the blades seems like its trying to spin but seem to go back and forth, is it suppose to do that? Any ideas would be greatly appreciated, I spent very little on it and got some other good stuff at a super cheap price so Im not too upset if I cant get it to work, Thanks