jeffaquarius
Aquarium Advice Addict
In designing the sump systems, there are 2 CRITICAL things you must consider.
1. Power loss. until the tank stops draining, the sump MUST be able to take all the overflow and backflow water without overflowing.
2. If the overflow stops for any reason, and the sump continues to return water, your DT MUST be able to handle all the extra water, until the return pump pumps the return section dry and burns out.
You have a planning issue with the second consideration. Even after you fix the anemone issue, you should really lower your DT level to prevent overflows.
My suggestions:
1. The return nozzle in DT should just barely be touching the top water level to prevent back flow to sump during brown out.
2. Install a low level cut off sensor to your sump so that pump power is turned off when water level is below setting. You can get an ATO with such feature. The pump may cycle on and off during the crisis but this will prevent flooding.