I noticed today that there is no suction at my skimmer. I have an inground pool with a cartridge filter. There are no special valves or anything to switch lines. The jet is working. the pump seems to be primed. i opened the pump and put the hose in and then turned it on and it sucks automatically. I have been scouring the web for hours and I can't find the info I need. everyone seems to have fancy pumps with special valves and stuff. Mine is very simple and probably old. I just moved into this house about a month ago. Please help. I put algaecide in the pool two days ago and just noticed today that the skimmer doesnt seem to be sucking at all. so the pool is still green and i cant vacuum or anything. Thanks in advance for any assistance. Also, the pool is filled to the appropriate level.