Terrible week

I've been in this hobby for 6 years, over that time I have had a couple relatively minor setbacks, but the past 10 days have been devastating.

After my tank transfer everything looked great, corals were open clam looked good and fish were swimming along. Last Tuesday I noticed a couple white spots on my Foxface, figured it was just sand. 2 days later a couple spots were on the yellow tang. They were only noticeable under the blue lights. The fish were all swimming like normal, no flashing or scraping. I've never really had a disease outbreak in the tank, and have not added anything new, coral, rock, fish for well over a year I just assumed it was the fresh sand sticking to them. 2 days later all of my larger fishes eyes were looking cloudy under the blue lights, obviously something was wrong. I bought a product called fish first aid from reefgrow, with the hopes it would help whatever was happening. 2 days later (last Saturday). My goldflake, female clown and Kole tang were dead. By Sunday the Regal angel, male clown bangaii cardinal, yellow tang and Mandarin were dead.
On Monday the Foxface had also died.

All I have left is my melanarus wrasse and yellow watchman goby, who both appear healthy, meaning their eyes are clear. All my corals and inverts are totally fine.

I have been testing my water, no ammonia, nitrite or nitrate was in the system.

I really don't think this was ich, although the dead fish were covered in very small white spots, almost like they were dusted by something. These spots appeared fairly close to death, nobody swam around with spots for a week or anything like that. All fish were eating well, until the day before or day of death.

Going forward, what should I do? If anybody has any ideas of what this could have been please let me know.


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I went with all new sand in this setup. Over the years I've lost plenty of coral, but very few fish. Even the old yellow tail damsel went down to this disease.
So......I know I should go fallow for a probably 2 months. If I do that, do I medicate the tank I transfer the two survivors into? Should at just leave the two fish in the tank and not add anything new for a few months? Are wrasse and gobys resistant to any diseases that would wipe other fish out?

There does appear to be diatoms or Dino's growing on one of the rocks in my new tank. Is that an indication of anything?


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I actually do, and did consider it.....briefly. What would I be looking for? I assume a parasite would move?


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I was looking at pictures and descriptions, yes the fish were swimming into the current. The spots looked like velvet. The confusing thing to me was with no new additions, how did the disease even get into the system?

Regarding temp....yes, there was a temp drop from 78 to 72-74 degrees a few days before the disease showed up. I have an old aquacontroller that only did my lights and heaters. Something went wrong with my temp probe, or the unit itself and it registers an extremely high temp on the display (127 degrees)
This prevented my heaters from kicking on for a day or two.


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Is this something that going fallow would help? Are the two remaining fish carriers?


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