Morphing Angels?

[tyr-sog]

I have read that this can be a stressful time for the fish and can cause death in some cases. Is this true?
I have had a Queen Angel now for 6 months and all was fine until I got home today in the afternoon(well I didn't check the fish in the morning anyways). I looked in the tank and noticed my 2 inch queens swimming in circles, disorienated. There's no signs of enternal parasites although yesterday I thought I saw a stringy yellow thing on her tail. She usally has stuff stuck to her all the time though from going in and out of the LR. Also there was no signs of abuse from other fish either. The only difference is I have noticed over the last couple of weeks she has started to morph in to her adult colors.
All paremters were fine, water temp is fine, tank has been up over a year, all other fish are fine, etc...

 

[beth]

Is she eating well? Breathing/gilling normal? If the answer is yes, I would simply keep and eye out on her. Use a magnifying glass to give her a thorough once over.
Do you have a QT setup? Just in case she is sick.

 

[tyr-sog]

Died over night.
Yeah I had her in a large net, she never did seem aware, floating, bobbing, swimming erratically. I examined her for awhile in the net and found no signs of anything. Rechecked my water and everything was fine...All my other fish are fine.