First off I started noticing last year a drop in return pressure. I have 4 return jets, 2 at each end and a 5th return for the "cleaner" right near the skimmer on the side. The cleaner is on its separate line. the cleaner line has tons of pressure, shoots out fast, the others have little pressure and bubble quite often.
I figured it was a filter pressure issue, but I'm currently running without filters just to circulate the water after opening and it used to shoot out really fast from the returns, now its still just trickling out/bubbling. Even when the cleaner line is closed.
Could I have a leak on my return line for the 4 returns? The 5th one works fine for the cleaner (separate line)