I think its that combination of no ato and strong pump. I will be putting the ato on soon. But yeah salinity went from 1.025 to 1.026 over a day or two so yeah thinking combinationI don't have that sump but your flow shouldn't change just because the socks are clogged. I see in the picture it has an overflow in the sock chamber. It should just go through the overflow and just not be filtered by the socks but the flow should be the same. Are you sure it's not because of no ATO