Okay, so I've been working with some ideas to octo-proof my hang on back overflow.
First I tried putting some filter screen over the U-tube, placed a slightly larger tube that fit snuggly over the end to hold the screen on, and it apparently interfered with the flow because the water pump in the wet/dry kept pumping it dry.
Next I tried chopping up a fish net with larger holes, and used the same method, to no avail.
Any ideas? The insight of people experienced with this is greatly appreciated.