Hello everyone I'm new to the hobby, I have a 90 gallon tank that has been up and running for 7 years and took it over from a friend. I have had the tank at my house for about 3 weeks it came with the water established and live rock. I added fish 2 weeks ago and everything has been fine up until 2 days ago, my porcupine puffer started getting lighter in color turning white pretty much. He is the reason I agreed to take over his tank I've always wanted one. All my levels are where they should be and lighting is good. I don't know what is going on with him and could use some help. My LFS told me it's probably stress but I don't believe that is the case. Any advice would be greatly appreciated I am a newbie and know I have a lot to learn. In my tank is a porcupine puffer, dog face puffer, Picasso trigger and a cow fish. Please help
My puffer has cloudy eyes and now seems to be purplish in color almost like his color is coming back just slowly.