stringy

I have some juvi peacocks and haps all water parameters good and the breeder said parasites are highly unlikely. Anyway I recently noticed one with long white stringy poop and he began to stop eating otherwise he looks fine (I'd assume caused by stress from shipping a couple weeks ago but I'm...

Noticing some fading on him, his orange tips are now white at the ends??? He seems very interested in food but spits it all back out after eating. He has long white stringy poop. And somewhat normal behaviors, been treating with melafix api, no help, any ideas!?!?