Overnight Disaster

AlaninVA

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Introduced 4 Banggai cardinals from Dr Reefs Q’d fish Thursday. Each about an inch long. Followed all instructions.

They were fine at first, by this am all dead.

40 gal breeder w/ Oase canister and a Octo 100 HOB skimmer. Salinity 1.024. Temp 77. Nitrate 11. Phosphate 0.31. Calcium 400, Alk 9.9, Mg 1200.

Other stock is an ocellaris clown, neon dottyback, 8 - 10 (now very well fed) hermits (blue/red/scarlet mix), and some snails.

I know my phosphate is a bit high and I am trying to bring down slowly as to not bottom it out.

What did I do wrong?
 

Pistondog

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Introduced 4 Banggai cardinals from Dr Reefs Q’d fish Thursday. Each about an inch long. Followed all instructions.

They were fine at first, by this am all dead.

40 gal breeder w/ Oase canister and a Octo 100 HOB skimmer. Salinity 1.024. Temp 77. Nitrate 11. Phosphate 0.31. Calcium 400, Alk 9.9, Mg 1200.

Other stock is an ocellaris clown, neon dottyback, 8 - 10 (now very well fed) hermits (blue/red/scarlet mix), and some snails.

I know my phosphate is a bit high and I am trying to bring down slowly as to not bottom it out.

What did I do wrong?
Params are fine, likely did not kill fish.
Can you detail how you introduced/acclimated fish?
 
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AlaninVA

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Params are fine, likely did not kill fish.
Can you detail how you introduced/acclimated fish?
Followed instructions that came with fish. Temperature acclimated for 30 min. Salinity in bag was within 0.001, (1.025 vs 1.024) so I poured out almost all bag water and added the fish. Had lights off for about 4 hours. After a while territory was settled; dottyback had his rocks, cardinals on another set. In evening when lights went off the cardinals were each exploring a bit on their own.

Thank you for suggesting that this wasn’t something I did. I don’t like killing things unnecessarily.
 

Pistondog

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I do not have a good explanation. A concern of mine with sumpless systems is gas exchange, but your fishload is low.
I have a couple of aio, and they have bubblers.
 

edsbeaker

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Introduced 4 Banggai cardinals from Dr Reefs Q’d fish Thursday. Each about an inch long. Followed all instructions.

They were fine at first, by this am all dead.

40 gal breeder w/ Oase canister and a Octo 100 HOB skimmer. Salinity 1.024. Temp 77. Nitrate 11. Phosphate 0.31. Calcium 400, Alk 9.9, Mg 1200.

Other stock is an ocellaris clown, neon dottyback, 8 - 10 (now very well fed) hermits (blue/red/scarlet mix), and some snails.

I know my phosphate is a bit high and I am trying to bring down slowly as to not bottom it out.

What did I do wrong?
I can’t help but wonder if the dottyback was not happy with his new tank mates? They are pretty territorial and aggressive and in my opinion it may have been better to put the cardinal fish in first.

Also, it is not unusual for a group of bangaii cardinals to kill off each other one by one, until the group is left as either a bonded pair or one sole survivor. As they mature they become more aggressive towards their own. I don’t think that was the case since this happened overnight, but just wanted to let you know that this could happen so that you could consider that before trying to add another group. Pajama cardinals get along fine in groups.
 
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AlaninVA

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I can’t help but wonder if the dottyback was not happy with his new tank mates? They are pretty territorial and aggressive and in my opinion it may have been better to put the cardinal fish in first.

Also, it is not unusual for a group of bangaii cardinals to kill off each other one by one, until the group is left as either a bonded pair or one sole survivor. As they mature they become more aggressive towards their own. I don’t think that was the case since this happened overnight, but just wanted to let you know that this could happen so that you could consider that before trying to add another group. Pajama cardinals get along fine in groups.
Thanks.

I might try pajamas in future.

Right now I’m going to work on getting phosphate a bit lower and get it and nitrate to flux less.
 

Mr. Mojo Rising

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There is no timing in your post so hard to tell, were they all fine yesterday and dead this morning? Did they all die at the same time? Die one by one? How did the bodies look? I am also wondering about the neon dottyback, they have aggressive reputations
 
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AlaninVA

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There is no timing in your post so hard to tell, were they all fine yesterday and dead this morning? Did they all die at the same time? Die one by one? How did the bodies look? I am also wondering about the neon dottyback, they have aggressive reputations
Seemed fine yesterday; dead this am. Hermits ate 3; only bit of skeleton left. I must have caught the last one before they could get to it.

Dottyback occurred to me, but it isn’t very big and didn’t seem to bother them unless they ventured too close to his rock.
 

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Oh yes - they already offered store credit (Dr Reef’s Quarantined Fish). They are a pleasure to work with.

My big concern is to make certain nothing on my side is causing the problem.
To me this sounds like shipping/temp shock. I doubt it’s anything that you did.
 

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To me this sounds like shipping/temp shock. I doubt it’s anything that you did.
I don't think we've been given enough info.

If I'm following along correctly, OP said he got the fish thursday, and followed acclimation procedures.
then found the fish dead on Sunday morning. The OP never mentioned anything at all about friday or saturday, so I'm going to assume that means the fish were fine on those days and he didn't notice any issues.

And if that is the case, that would seem to rule out shipping/temp shock.

How were the fish acting on friday and saturday?
swimming and breathing OK? any signs of trouble?
were the fish eating? any flashing or scratching on rocks?
any aggression from the dottyback or other tank mates?

Just to confirm, these were fully QT'd fish from Dr. Reef? and not just conditioned fish? because he does sell both conditioned and QT'd fish now.
 

Jay Hemdal

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Introduced 4 Banggai cardinals from Dr Reefs Q’d fish Thursday. Each about an inch long. Followed all instructions.

They were fine at first, by this am all dead.

40 gal breeder w/ Oase canister and a Octo 100 HOB skimmer. Salinity 1.024. Temp 77. Nitrate 11. Phosphate 0.31. Calcium 400, Alk 9.9, Mg 1200.

Other stock is an ocellaris clown, neon dottyback, 8 - 10 (now very well fed) hermits (blue/red/scarlet mix), and some snails.

I know my phosphate is a bit high and I am trying to bring down slowly as to not bottom it out.

What did I do wrong?

Well, it’s not you water quality, but did you test ammonia if it’s a new tank?

Were they fish feeding well at first? If so, it was not an acclimation issue - that’s an acute problem that would show up on day one, not day 3.

Did all fish die overnight with no prior symptoms?

Did the dead fish show ripped fins or gaping mouths?
 

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