Why did this happen?

I went to feed the broodstock this evening, and one of my best breeding females was lying motionless at the bottom of the tank.  Beautiful large brightly colored ocellaris, just spawned a nest 3 days ago, eating well this morning, lying on the floor with gills extended, dead as a doornail.  I am both sad and mystified. I've had her for years, in fact she and her mate were progeny of a pair of my own fish. Perfect in every way. Except dead.

I'm really sorry to hear that, Kathy.  I'm afraid alll I have to offer is my condolences.

Sorry to hear it Kathy. I'd be more than happy to offer one of mine if you want some different genetics. Just let me know.

RLTW

180 Gallon Mixed Reef

Then I heard the voice of the Lord saying, "Whom shall I send? And who will go for us?" And I said, "Here am I. Send me!" Isaiah 6:8

That's very kind of you, but this was a pair I had hoped to sell, because it was so beautiful and healthy. Humph.  I'm fine without the pair, but darn, I can't figure out why she died.

So sorry to hear. I hate to lose any fish. Do any of the other fish look stressed?

http://www.fishtalpropagations.com/#!home/mainPage
"Making captive breeding easier."

No, I have 6 other pairs on the system, and they all look great, and several about to spawn right on time.

I imagine fish can "drop dead" just like people can of various different things.  Heart attacks, aneurysms, who knows?

Some time ago, I went into a store that buys from Sustainable Aquatics, and found a tank of orange ocellaris with 7 or 8 fish in it.  One was plump, as though she was gravid, and one was aggressively keeping all the other fish away from her.  I got the pair, thinking they would spawn soon, but of course, I was way off.  It took months for them to spawn, and they chose to spawn into a place in their tank that I could never harvest the eggs, and I never bothered to  capture the larvae.
 
The little aggressive male started to turn black. Now he is mostly black, and resembles an imagined cross between an orange and a black ocellaris.  Not great genetics in my opinion.  Sustainable is now marketting a Transformation ocellaris that does this color change thing.  I think he is one of them.
 
I moved the beautiful bright orange Sustainable female to the remaining male and eggs from the deceased female described above.   The male is not very much smaller than the female, but I think the presence of the dead female's eggs eased the transition.  They squable a little, but a few days after the old eggs hatched, the introduced female laid a big beautiful new nest on the pot, they are fertilized, and its as though the introduced female is on the schedule of the dead female.  They wasted no time.  I look forward to raising these!  Some good has come out of it!

That's awesome Kathy!   That's some luck there!

Don't let fear and common sense stop you! =]