Yesterday I mysteriously lost 4 fish within 12 hours of each other:
- fox face
- Blue tang
- Yellow tang
- Coral beauty
- 180 gallons
- Established 1 year ago
- Has various sps and a red bubble tip anemone
- Fish that survived: purple tang, flame hawk, engineer goby, 8 blue springer damsels, 2 clowns, 4 shrimp and 2 star fish
- Sump setup with a Refugium and carbon reactor, 2 maxspect gyres
- 3 ai hydra 26 Lights
Everything was completely normal until Saturday morning when I found Fox face dead. No apparent reason. Blue tang was hiding in some rocks and didn’t look good. A couple hours later he turned up dead. Other fish looked fine. Couple hours later coral beauty croaks, followed a few hours later by yellow tang. All these fish were FINE the night before.
- 1 week prior I added hakari discus
cubes to my hikari mega marine algae and brine shrimp cubes. I feed a total of 3 cubes once per day and half a sheet of algae
- 1 week prior, and at the suggestion of my tank cleaner guy from LFS, I setup my carbon reactor and got it going again... I hadn’t been using it for a while. He said corals looked stressed so he suggested the carbon.
Things ruled out:
- I took the water to the LFS the day of the event and everything tested fine
- Heater didn’t break and fry the fish
- I used a multimeter to test for an electric current in the tank... nothing.
- All the filtration and pumps have been running fine the whole time.
- My wife left the back door open a day or two before the event and a lot of bugs (gnats, flies, mosquitoes) flew in. They are always drawn to the fish tank lights and end up in the canopy. Could some toxic bug have fallen in and been eaten?
- Could the fish food have been bad? Spoiled, infected with something?
- My tank cleaner guy added a bunch of alkalinity booster a week before... could that have killed them?
I’m really stumped and worried the mass die-off isn’t over. Would greatly appreciate any help figuring this thing out.