I've got what may be an issue with air bubbles in the return water jets. When the filter first starts, there is a large amount of air in the lines which reduces after a few seconds but a steady stream of small bubbles persists for as long as the filter is running. When the pump stops, I can't hear air/suction noises at the filter/valve/pump yet when it next runs after a few hours, the air is there.
Obviously there's a leak somewhere, but is there a usual culprit? I'm new to this, the pool came with the house we bought and have been here since just before Christmas.
I'm not particularly concerned abut it, but I've read that the pH can be raised because of it which appears to be the case here.
Any advice before I call the local pool shop to come and have a look?