Help Fish Dieing

[KrazyKuch]

My Signapore angle is dieing and I need to figure out how to save her


Last night everything was fine she was swimming around like normal didn't notice anything wrong with her.This morning when I woke up she was lieing on the sandbed(this was at 5:30am no lights on I thought she was sleeping). But when I got home this afternoon I noticed she was still lieing in the sand not moveing just breathing and she had some discoleration on her body, all paremters are normal although I have notice a little bit of ich on some fish.....What happened and what can I do to save her??