In my experience its a snake by snake thing- and usually prolonged soaking isn't building/breeding related. Some girls are just somewhat aquatic. If your relative humidity is 55-65% and there are no signs of mites and the animal soaks like crazy (consistent with no correlation to shed cycle (days at a time)) I would suggest (if your worried) to get a fresh fecal sample to get labs done for internal parasites. Most exotic vets will supply you with the plastic samplers - free of charge- in hopes that you'll bring them fresh day old poo to run the labs - about $25-$35.