I sincerely hope someone can help me figure out what has happened to my tank. I have a 75 gallon with a Fluval 406 canister filter and a Coralife skimmer. Last Sunday (a week ago today), I noticed that all of my fish went VERY suddenly lethargic, staying in one spot near the bottom and not acting normally. They were all fine earlier that same day, eating, grazing on the rocks and their normal happy selves. I immediately knew SOMETHING was wrong, so I ran a full test of the water, suspecting that some parameter was amiss. To my surprise, all tests came back completely normal...SG
1.024, 0 ammonia, 0 nitrites, 5 or less nitrates, pH 8.2, Kh
10, phosphates near zero, calcium 440. But just to try to be safe, I put fresh carbon in the filter, added a couple of bags of Purigen, and changed 10% of the water and went to bed hoping the fish would be OK. But it was not to be...the next morning they looked even worse, so I changed the carbon again, did a 40% water change, checked water chemistry again with the same good results. No improvement by the end of the day, but hoped for the best the next morning. This time, several of the fish had died during the night, and ALL of the rest of them were dead by the end of the day. An examination of the fish showed nothing unusual...with the possible exception of maybe a bit of "mistiness" on a couple of them...
I lost a yellow tang, flame angel, purple firefish goby, a 6 line wrasse, a clown and my beautiful mandarin goby...everything.
Here is the strange thing, however...I have about 50 lbs of live rock, 2 inches of Bahama live sand, a curly anemone, 2 cleaner shrimp, 1 red fire shrimp, an arrow and emerald crab, a sand sifting starfish and some softie corals...ALL of which were unaffected by this disaster...very peculiar to me, because the inverts are usually the first to go when something goes wrong, but they are all alive and thriving here a week later.
On Friday, I visited the LFS
with a water sample and hopefully for some advice as to what could possibly have happened in such a short period of time...I even brought the deceased fish with me (I had frozen them for inspection), and the LFS
owner could not detect anything at all wrong with the fish OR the water. At this point the tank had been barren of fish for 3 days, so he suggested to try a couple of tough damsels to see if they would get sick and die as well. So they were added to the tank Friday...one died today with the exact same symptoms and I expect the other to be dead by morning.
What could possibly be wrong with my tank? Why would ALL of the fish die and NONE of the corals or inverts? And even scarier, whatever is causing this is still there, but can't be identified?
I PRAY someone can help...please ask any questions that would be pertinent to helping me solve this mystery. I am sick to death and totally depressed over losing all of my fish and no answers as to why