shao,
Most of them were 3" and slightly under. The Lamarck's was about 4". You are correct that there were no fish in the tank previously, only astrea and margarita snails for a clean up crew.
The tank had cycled long before the 2 months had passed. I had it prepped for more seahorses that wouldn't become available for quite some time. During that time, we decided fish would be a better choice in a tank that large. The angels were actually a birthday present for my husband, so the loss hits a little harder
After the tank cycled, fed the tank chunks of frozen food placed in two small drinking glasses at either end of the tank. When one chunk had disintegrated, fed another chunk. Had macroalgae to soak up the nutrients, but there was a good amount of algae on the glass that I kept cleaning off. Also did water changes every 2-3 weeks.
Have a pH probe and used it to monitor pH change while slowly accclimatizing the fish to the tank's water. Took about 1.5 hours to acclimate them in a 5 gal pail with powerhead.
As I said, checked params this morning to determine if the increased bioload had anything to do with their deaths. Ammonia, nitrite and nitrate all were 0 ppm. After the fish were introduced, began to do weekly 15%water changes, filter cleaning, etc., so I was on top of maintenance issues.
Usually, I buy fish from the lfs that quarantines them for 2 weeks prior to sale to the public. Didn't do that this time. Almost never quarantine fish, either. Bad practice, I know, but over the years in a variety of reefs have only had a fish here and there die. Never had anything close to a complete wipeout like this until now
Sh*t happens in all kinds of reefs for all kinds of reasons and this time it happened to us in this way, is the way I look at it. Still shaken up, though, but want to move forward when the time is right ...
What happened to your angels, and what kind were they? In how big a tank?
Would appreciate your stocking suggestions.