I got through moving my tank and had installed a DIY sump under the stand. It was made from glass tank with acryllic baffles siliconed into place. I had tested it a bit with fresh water before installing and the baffles were leak free. In preparation for connecting the sump to the main, I had set it up to mix some SW
with my return pump cycling water to the return section using a PVC
loop. However, a few days later, I am noticing a white film on just about everything in the sump and I have no idea what this could be from. I have not added sand to the refugium yet, so it should not be silt. Could it from the plumbing or something from the silicone? I was certain not to get mildew proof silicone. What should I do to clean this up before connecting to the main?