Just got my PSK-75H yesterday and it's up and running. Last night the water level was at the bottom of the collection cup. This morning the bubbles/water is 3/4 up the collection cup tube even with the return wide open. I also notice a gurgling/trickling water sound of the water going into the intake. Is this normal and will it eventually subside? Is there anything I can do to stop this? What can I do about the water level in the skimmer?