Ok, I'm not sure "how" I measured the deli cups earlier, but they are actually a bit LESS then 4 inch across the bottom. So I'm getting the 4 inch PVC couplers tomorrow, and then I will fix up the new tubs, let the silicone cure, and move the snakes into the clean, new and improved tubs

Then I can deep clean and scrub the old tubs and keep them as spares..

I'm looking forward NOT to have all that soaked aspen from spilled water in freshly cleaned tubs