So I decided to buy two mystery snails for my divided 10 gallon, named Dave (the big one) and Carl (the small one).
Even in the bag, Dave was secreting stuff, and it seemed like he was sick or stressed. I put him on Eris's side, because that betta is definitely more chill, and I figured Dave needed a low stress environment - I even acclimated him way longer than I ever did for any of my bettas!
Carl was perky from the beginning. When I was acclimating him to the water, he was out waving around like Whooo!
And then, in the Kraken's side, he was out and cruising around, even when the Kraken started to circle him. He was all like Whoo, hi neighbor I'm a snail! Yaay!
Then the Kraken viciously attacked him, tearing out huge chunks before I rescued Carl and put him on Eris's side
The two snails were in the tank, side by side, overnight, and the next morning they hadn't moved at all. So I wondered if Eris was secretly harassing them since he kept flaring at them before (why?? DO THEY LOOK LIKE BETTAS TO YOU ERIS). In any case, I switched them out to their own container and changed the water frequently to help them heal.
They died the next day
No invertebrate I try out ever lasts more than 24 hours even with the freshest water ughhh, and seeing the Kraken live up to his name was just sad. I know snails are typically recommended as a good betta companion, so I was wondering if anyone else had any stories that suggest otherwise!