I picked up a Flameback angel from my lfs today, and acclimated it for an hour adding water from my tank to the bag it was in every 10 min. I added it to my 25g with a clownfish and a bicolor blenny. It swam down to the bottom part of the tank and stayed hidden in a cave for a couple of hours. 4 hours later the fish is becoming more comfortable in its new home and is swimming around exploring the tank. Then I cut flow to feed my fish and the angel swims to the top peaks it’s head out of the water like my clown does when it knows it’s time to eat. All of the sudden my new fish stopped swimming and floated down to the bottom of the tank and died. Im devastated I have no idea what happened or where I went wrong. Could anyone let me know if I did something wrong? Maybe it was too stressed? Maybe I got a sick fish? I’ll appreciate anyone’s input.