My tank has been running for about 6 weeks. I have adjusted my flow to and from my sump so it is silent but about every 2-3 weeks it start to get noisy. It seems the return flow slows down after a few weeks. I have to re-adjust to get it quiet again. Is this normal? Could it be the return pump breaking in? I had a tank with a sump a number of years ago but don’t remember this issue. I do have an ATO so my water level in the return chamber stays constant. My overflow is a EShops S and return pump is Sicce silent 2.0.
Any thoughts?
Any thoughts?

