input requested. tank crash: fish dead, coral ok

[redwhiteandblue]

to sum everything up, in 7 days i lost 13 fish. i have one tang left, but will be gone soon. all coral appear to be normal, this includes softies, lps, and lots of sps.

tank info: 140 gallon, skimmer only

my first thoughts are bacterial/ parasitic as most of the fish had a white spots/ slime coating followed by rapid breathing and death shortly after symptoms. fish deceased mostly from smallest to largest.

small clows, mandarin, dottyback, gramma, tonini tang, flame angel, more clowns, etc...also clean up crew consisted of about 5 crabs. have not had purchased any in years, these were the remaining ones. i have not seen any in the tank in a while.

here is the kicker....i have added 0 livestock since june (no coral, no inverts, nothing. since then, i have broken the tank down, moved 30 minutes away, set up in a stock tank, and then set up again in an 8 footer. 0 losses in both tank transfers, no signs of stress, no white spots or slime, no issues at all. i would have thought if my fish were in fact hosting a disease for so long, it surely would have shown up during the transfers.

everything was fine through november and up until about a week ago.

so my first assumption of a parasite doesnt line up too well, and leads me to possible contamination of the tank via metal/ chemical. although i cannot think of any possibilty of chemicals as tank is in basement, and our most common cleaning product is vinegar and water. that is where i am at a loss. could it me my hammerhead mag float leaching? heaters?
totally clueless/helpless on this one.

my water quality/ maintainance has been lacking, but as mentioned corals are normal/ better than usual so...? ammonia 0, nitrate 0, and some hair algae issues. PH range is 8.1 day/ 7.8 night and this has been the norm for 4 years.

thank you in advance, any suggestions are welcomed.

 

[iluvmyfishes]

If you added any inverts or fragments it could have come in on those. It sounds like velvet or something like that. Did you QT the tang yet? I had something similar happen in my tank last year. I put my fish in QT but still lost them, it was so fast. I left my DT fishless for over 6 weeks but as soon as I put another fish in it, it got sick. So I ended up putting all the corals and inverts in a QT and treating the DT with Cupramine. I used my DT as a QT for all my new fish. When I made sure my new fish were healthy, I removed the cupramine, eventually added back the inverts and corals and now I have a healthy DT again. It was the only way to fix whatever had gotten into my tank.

 

[redwhiteandblue]

If you added any inverts or fragments it could have come in on those. It sounds like velvet or something like that. Did you QT the tang yet? I had something similar happen in my tank last year. I put my fish in QT but still lost them, it was so fast. I left my DT fishless for over 6 weeks but as soon as I put another fish in it, it got sick. So I ended up putting all the corals and inverts in a QT and treating the DT with Cupramine. I used my DT as a QT for all my new fish. When I made sure my new fish were healthy, I removed the cupramine, eventually added back the inverts and corals and now I have a healthy DT again. It was the only way to fix whatever had gotten into my tank.

I have not added anything to the system for 6 months. No signs of anything since.
No gonna bother with qt the last remaining fish. She is going through what the others had, too quick, and too late based on my experience.

I would suspect velvet or brooklenella, but how is it showing up now? And not during two tank transfers...

 

[redwhiteandblue]

Bump

 

[slief]

Your fish had white spots?? I think you have your answer right there. Your culprit was likely ich or some other parasite but I suspect ich. Just because you haven't seen it, doesn't mean your fish weren't carrying it.

From the sounds of it, you are going to loose your remaining fish. I would suggest you keep the tank fallow for several weeks and QT and treat any new fish for a number of weeks prior to transferring them into your display. That is your best method of avoiding this in the future.