Weird Bladder Snails

[Flying Fang]

I’m new to planted tanks and have done as much research as I could to make sure I did everything right. In my 20 gallon tank I have: 1 Betta, 1 Oto catfish (I’m trying to get more for a small school, but the local fish stores have been out of stock), and a ton of what I assume to be bladder snails.
 

The snails seem to be doing well, except I noticed that three of them have clear shells and a red body. Should I be concerned? Is it an illness, or just a form of albino? 

Edited June 10, 2021 by Flying Fang

[Sarina]

Could be ramshorn snails, too. Albinos have clear shells and red bodies. If you're concerned they're not getting enough calcium, you can always add a wonder shell, they're very inexpensive and they work very well. 

[Griznatch]

Bladder snails are almost bullet proof (unless they run out of food). although some see them as pests I have seen some pretty beautiful shell patterns on the ones in my tank. Also when smaller, ramshorn snails can look kind of like bladders and they definiely can have red body or "feet"....

[Flying Fang]

Double checked and compared them to pictures and I think you are right with them being ramshorn snails. Glad I don’t have to worry! I already have sea shells in the tank and have heard that snails will sometimes get calcium from eating other shells. Will that work if I don’t get the wonder shell? The water is also pretty hard (but still in safe perimeters) too.