| Here is some backgroun....maybe this will help:
The water was getting a bit low. So I went to the garage where I store my treated salt water. I have a 58 gal tank and only added about 5 gal. The water I added was probably a bit cooler than the water in the tank.
I also had a yellow damsel and a tomato clown. I noticed that a couple of days after adding the water the yellow fish was dead, the tomato MIA (dead under a rock or lion food??) and the Lion had white spots.
I tried to feed my lion but he wouldn't eat. He was interested but all he could do was lunge for it and didn't really open his mouth at all to get the food. It was like he had lockjaw or he did eat the tomato and couldn't fit anymore in his mouth.
After I noticed the spots, he went downhill FAST. I saw him shed the next day. Then he seemed to be covered in more spots then I saw the ends of his tail missing and losing color. It was like his skin was rotting or melting away.
I don't know if there happened to be something that got in my water. ( I don't know what ??) Or what happened.
My choc. chip seastar is still doing great as are my mushrooms.
Any advice would be greatly appreciated to help me figure out what I did wrong. I'm still new at this and my tank has only been set up for about 6 months (I bought it off someone so the water and rock and fish came with it) | 
