@alovealoe thanks, it's so hard to know with watering because different websites/people give you different advice. I will trust yours and stop all watering for the time being. When I got my other pot of Lithops it was so damp moss was growing in it, so I thought I must not have been watering mine enough and it made me water more, and then this happens! Argh. Are they too long as well? They probably don't get enough sun.