How much of a bio load do snails have? Or are they like shrimp and it's pretty much nothing?
It really depends on the type of snail, and the amount of them.
I'm looking at mystery and nitrite for my ten gallon betta tank.
IME, mysteries produce more waste than nerites. If you do decide to add mysteries, just keep an eye out since your betta may try nipping at their antennae and fleshy parts as they're more exposed than nerites.
A fully grown Mystery Snail Pomacea diffusa Needs about 2.5 gallons per snail, though many use 5 gallons to be safe when considering the bio-load from their uneaten food (residual left in the tank). Nerites are a lot smaller and are very keen algae eaters and only need about 1 gallon per snail. I had a very territorial Betta that would display over his own reflection then be aggressive to the snail I had in there, maybe because he was already flustered and needed to work off his anger? lol I would just keep an eye on them. I don't see any other parameters on your 10 gallon, so hard to say more than this. Good luck!
Thank you. That was exactly what I needed to know.
Just to add on to what rainman said, ime, I find the 5 gallons per snail to lead to happier, healthier snails for mysteries. Nerites are very light on the bioload.