We have a very, very large hairy Australian acro that we've had for a while in our well-lighted, well-established almost 10 year old reef. Nothing has changed in this tank but over the past couple of days but this acro went from a rich emerald green thriving coral to an almost dead, except for a few tips, coral. You can almost see it happening right before your eyes. What, pray tell, can kill such an acro literally in days?
that is very sad to hear. I've not experienced that myself, but seen many people post similar experiences. I know that in ULNS ALK swings, and more specifically low ALK can wipe out a coral pretty fast, but usually it starts with bleached tips...
RedBugs and AEFW can do bad things too... but I'm assuming you'd have checked for those already...
Definitely not parasites but possibly a dkh fluctuation. Man, I'm really, really fed up with this aquarium. >:(