This breeding group of multies has been together for 8+ months. In the last two months, the area around the anus and ovipositors has gotten "inflamed", but I chalked it up to not enough food. With slightly heavier feeding, the increased bump in that region has remained. More recently, one or two have developed large red bumps internally, perhaps from a blockage? Any ideas what could be going on?
pH 7.3, average hardness, temperature can get up to 83 but usually around 80.
Well that is very odd looking, I wonder if the fish ate one or more of the snails and the shell is stuck?
You could try mixing and adding some Epsom salt to the tank to help reduce swelling but don't know if that would help if it's eaten snails. The usual recommendation is 1tablespoon of Epsom salt to 5 gallons of water, dissolve in water before adding to the tank over a period of a couple hours.