Tank move, QT issues, fish dying - any thoughts?

[bdturtle21]

I recently moved my 55 gallon tank to our new house - it was only about a 1 hour move. I had a QT tank set up at the new house (20gallon long) with PCV pipes for hidey-holes for everyone. All fish took the move well and even ate their first night in the QT.

(I can go into detail on how I moved everyone if needed... but I spent weeks reading and preparing for the move - it was about as well planned as moving a reef tank can be...).

The evening of the move I pulled all the old sand out of my DT, replaced w/ new sand, and replaced the water (same water, just moved). The next day, once the sand/etc had settled I added the liverock (~40lbs) and put my corals (LPS and zoas) back into the DT along w/ the hermits, snails, sandsifter, and urchin. All are doing great and for now the water parameters are normal. (The corals/zoas actually opened back up within minutes of being in the DT).

All seemed to be going well...

My fish in the QT were doing really well, until mid-day yesterday. I noticed they were all (all but the clown) breathing heavily, so I added an airstone. This didn't help, and overnight everyone got worse. I immediately moved them to the DT. The clown is still doing well, but I have lost one of my firefish (bonded pair - yes I know, that rarely happens it seems, but these guys have been bonded for >6 months and were my favourite fish in the tank). My yellowtail damsel is in really bad shape and I think I will euthanize him this evening, if he doesn't improve.

There are no external signs of disease, other than super stressed fish, hyperventilating, and sitting on the bottom of the tank.

While the fish were in the QT I did cover them with a towel - the room they were in was really bright, and I thought the light (at night) might stress them more - so I covered them up. Could this have messed with the gas exchange and caused the issue?

All parameters have been normal in the QT:
ph=8.4
Alk=3.9
Nitrates=0
Nitrites=0
Ammonia=0

(Parameters are the same in the DT now, and I am monitoring in the AM and PM.)

I was hoping to leave the fish in the QT for at least a week, but clearly that wasn't working.

I do not know what went wrong, and I would really like to figure it out so I don't EVER make the mistake again. I really, really don't like losing fish - they are my responsibility, and I really struggle with knowing they came from the wild, rely on me to survive, and I couldn't manage to keep them alive during what should have been a relatively simple process.

Any ideas, suggestions, etc would be very welcome.

Thank you!

[mitchrapp]

Before adding the airstone, did you have anything else in the QT for aeration? Powerheads?

[bdturtle21]

No - no powerheads. HOB filter rated for a 50gallon and the water was well below the return, so lots of surface agitation. From what I read, it didn't seem like I needed more.... as soon as I saw the heavy breathing (within an hour or two of it starting - the fish were completely fine in the morning, and by 10am were breathing hard), I added the bubbler. I expected things to improve within several hours of running the airstone, but they progressively worsened.

[rffanat1c]

I had the same issue doing ttm. No one here could figure out why the fish were dying but I saved one by tossing him in the DT and he recovered

[stingeragent]

Did you check the QT for ammonia? What water did you use to fill the QT? Tap or Ro/Di?

[Yellow Eyes]

What was the salinity of the QT? Did you do any acclimation before adding the fish to the QT? What was the timeline from adding them to noticing the shortness of breath (I know you mentioned it but recently moved and "until yesterday" could be 1 day, or 3...just looking for a more exact figure)

[ReefGuy77]

Sorry you lost your firefish, but hopefully everything else recovers. I know you said ammonia was 0, but if you added all the fish at once to the QT, you would be adding a lot of bioload at once. Maybe the QT was starting to re-cycle.

[bdturtle21]

Yes, I did check ammonia in the QT - in the morning and evening for the 2 days the fish were in. I used RO/DI water for the QT tank and made sure it was the exact same salinity and temp before adding the fish. The QT was up and running for 3 days before we moved and added the fish.

[bdturtle21]

Salinity was exact same as the DT - 1.023. I did acclimate though, just to make sure the temps were the same (since the fish were moved, I worried that the temp dropped in their 'travel tote').

I expected the QT to cycle, since I added all the fish at once. That is why I checked the water chem twice a day - I was prepared to do a major water change if needed...

After moving the fish back to the DT, I've only the lost one firefish. The mate is still alive, but looks terrible. (These two were my favourite in the tank - I'm pretty sure they were mating before I moved the tank. . . I had grand ideas of getting them their own tank and trying to hatch ... I know, long stretch, but still a dream.)

I am fairly certain my yellowtail damsel is also dead since last I saw him he was on his side, hyperventilating, and being blown around - the hermits were after him. I almost pulled him out and euthanized him, but decided it would be more stress on the others. My scooter blenny is still unaccounted for.

I have no idea what happened, but would really like to figure it out (if at all possible) so that in the future I can prevent this tragedy...

Thanks to everyone for your comments!

[bdturtle21]

Sorry, timeline: the fish were in the QT for about 48 hours before I noticed them breathing heavily. Initially, I was going to only leave them in the QT for 24 hours, until I got the DT set back up - but everyone was doing so well I thought I'd leave them in the QT while the DT cycled (since I assume it is going to big time, after the move). Now I wish I had just gone ahead and moved all the fish to the DT, even though they looked great in the QT...

[cambo123]

bdturtle21, I moved about 3 months ago (approximately 2 hours). I had the exact same setup on the other side (20g brutes). Within 48 hours I noticed heavy breathing, lost 2 firefish first (bonded as well!!!) and my favorite clown of nearly 4 years (absolutely devastating). Everything else made it through after immediate movement to the display. I attributed it to low oxygen in the auxiliary tank although I may never know...best of luck.

[bdturtle21]

Cambo123 - I am so sorry you lost your bonded firefish too!! I loved mine. . . they would come out of their hidey-hole when I talked to them... And your favorite clown - that is SO hard!!!

I think my second firefish will not make it through the night.

I did end up euthanizing my yellowtail damsel, and did a skin scrape and gill clip - no parasites present. Though the gill morphology did look suboptimal (blunted, and a bit erosive) - so I am wondering if there might have been some sort of toxin present in my QT system.

From here on out I think I will stick to aquacultured fish only - it won't make losing someone any easier, but at least I will know what my ecological footprint is/was.

I also think I want to start another discussion - about QTs and the types of aquaria, HOB filters, etc... it seems the most common thing is to go out and buy the cheapest you can - makes me wonder about toxins/contaminants... maybe we all just attribute losing fish to something like low oxygen when really there is another variable...?