Puffer may be sick help

[Jlemayy]

I bought a dog face puffer yesterday also bought 20 gallons of water right from the same tank hes been in at the store so I wouldn't have to take a chance messing up the water mixture. I put him in the new tank last night he was very active but this morning he's is just laying at the bottom of the tank with his tail curled up ... I put some krill in there he ate some of it and left the rest i tried to post a picture the website says the file is to big but does anyone know if this is normal could he just be getting used to the new tank ?

 

[Neptune’sCollection]

Hey man, your pictures posted, idk if you can see it but I can. I’m new to saltwater, only been doing it a couple years, but First thing you should do is check your perimeters, it doesn’t matter to much about the 20 gallons you bought from the store if your tank hasn’t cycled completely and grew the bacteria. Check those and your temperature as well as salt/gravity. He looks like the only one in the tank but he could still be stressed( which is what it looks like). If perimeters Are good and stress is the issue then get a bigger cave for him to hide in so he’s not out in the open. Turn the lights off and just check on him periodically to make sure he’s good. He’ll just hide there out in the open till he dies and rots brother.