In that long thread , explain simple way to identify, most of the time i am very optimist, but to me looks like Dino.
Use a feed pipette to collect a sample of that crazy brown bubble hair Algae , put in one drinking cup , use a straw to mix , until the sample spread on may parts, wait few min. if she regroup, just like before, most like it is Dino, also use a cheep scope, is easy to see.
If , your snail most of the time wont move around, just stay in one corner , do NOT add more, there are more then 2200 species of Dino, some easy to deal some very hard to kill. Increase water flow , use filter sock, clean every day for a week, blow that hair from rocks, siphon first coat of sand, to remove most of the algae, decrees lights time, if is coming back ( i hope NOT) then you have to use that antibiotic.