Hello, new here. I had fish growing up and I am just now getting back into it. I just started a new tank 12 days ago. I made the mistake of getting fish 3 days after starting the tank and sadly lost both Molly fish after 2 days. After losing the fish I did a 50% water change and added Tetra Easy balance and aquarium salt. I let the tank run for another week and just added new fish after testing the water at home and having the fish store test it as well. All perimeters are supposedly just right. After one day my black Molly is swimming around happily and eating well. My Creamsicle Molly is displaying what I think might be shimmying but I think he came from the store that way, and my gold panda Molly is spending quite a bit of time sitting on the bottom of the tank. He comes and swims around in little bits and eats well. Then goes back to the bottom. I just changed the water a week ago so I’m nervous to change any of it again yet. I’ve only been feeding once per day to start. Ammonia, nitrate, nitrite, chlorine all 0, ph 7.5, in CO we have hard water. Alkalinity a little on the high side. I added quick start back on the 14th, added stress coat today when I saw the panda displaying bottom of tank behavior. My Creamsicle also came with a weird kink in his tail from the store ( Wish I’d of noticed before I bought) so I’ve been contemplating removing him from the tank. Would really appreciate help in what to do. They’ve only been in the tank for less than 48 hours so I know it’s early. It’s a 10 gallon tank. Temp is at 78 degrees. I attached a picture of the tail concern.