Turbo snails coming out then closing up.

Hi, I have a 20 gallon truvu with 2 black ocellarus clowns, 2 domino damsels, pistol shrimp & watchmen goby, fire shrimo 10 blue legged hermit crabs and 2 turbo snails. I got the turbos and crabs so they can help with my diatom problems. When i first put the snails in there. they were moving around eating for about 2 hours. then the snails became less active so i thought they were still getting used to the chemicals in the water so i let them sit overnight and one was on the wall and the other upside down poking out then hiding like it was scared. i flipped him back over and haven’t been back home to see how he’s doing. Is this normal, should i keep an eye on them incase they die?

nitrate: 10
phosphates: 7
calcium: 420
alkalinity: 8
nitrite: 0
ammonia: 0
salt: 1.025

I do need to bring up the phosphates a little bit but to my knowledge it all looks ok.