sorry to hear about the fish
Was there any way to intervene? por was it too late when you seen the goings on?
on your drain into the sump. Did you get the sump noise cleared up? I too am stuck with one drain hole in my tank. If I knew how easy it was to drill a tank before I started, I would have drilled it. But alas, Im stuck. I have a Durso style drain. with the ail vent up top. I also tried the T style thing down at the sump, to let the air escape instead of going into the sump with the water. I found it was noisy. The upright tube was like a megaphone. Did you have success with it?