Hi, It's been 1 mont I got a fish tank. I have guppies and pink zebra. Intially zebra was chasing guppy a lot and I did multiple things and since last 2 weeks they all get along well. Yesterday Evening 1 guppy isolated itself in a small house like structure I have kept in the tank. It didn't come out till now it's been 14 hours. I tried to see it properly and to my surprise its tail is colour less right now. It has lost color overnight. I changed water as well. Other guppies are fine but not eating enough. The one that isolated itself is not eating at all. Kindly help.