Dottybacks dying...all others fine

[smnw10]

Background: newer tank setup. Cycle completed 4 weeks ago. Put 2 clowns in, have done just fine. 10 days later put in CUC...no problems. I have all Marco Dry Rock with a little LR to seed and the marco rock is grown coraline algae on it already. 58 gallon tank, 90 pound of rock in this tank. Fuge and sump setup.

Water Temp: 78 degrees
Ammonia: 0
Nitrite: 0
Nitrate: ~10
Calcium: 480
PH: 8.2

After the CUC I waited 2 weeks then bought a Coral Beauty, a Yellow Watchman Goby, and a Bi-Color Dottyback. The LFS said the dottyback had been picked on and it's tail was partially damaged, if anything happened they would refund/exchange for me. So I thought I'd give it a try as I wanted a dottyback and liked this one otherwise. Well, the fish didn't make it.
After acclimation, they all 3 went into the tank, all 3 ate and swam and seemed happy. about 36 hours later the Dottyback was "gone" and I later found it in one of the holes in the rock (marco rocks are FULL of holes) dead.

LFS didn't hesitate and were going to refund but I wanted the fish, they didn't have a bi-color but did have a Fridmani Fridmani - Aquacultured so I paid the difference and got that one. Seemed perfectly happy in the tank when I put it in Friday evening. It ate and played in the rocks, all seemed well. Even Saturday the first part of the day, same thing, swimming, eating, no problems. Didn't come out Saturday night and couldn't find it Sunday morning. It did not come out to each Sunday either and the skimmer was going pretty good. Worried I moved around some of my rock looking for it but can't find the fish anywhere (have a tight fitting lid). It's not in the overflow or sump or anything either. No luck finding/seeing it this morning either...assuming it died and is stuck in a hole I can't see or the CUC got to it.

Do these fish have an issue with getting stuck in holes in rocks and dying or am I missing something or am I getting poor livestock???

All the other fish are doing great, the angel, clowns, and watchman. All eating, swimming, and appearing to be healthy and happy. The dottybacks looked great for 36 hours then poof, gone.

Before I go back to the LFS today to see what they have to say, I wanted to know what you all thought.

 

[smnw10]

Maybe someone can comment to this...
I went over to the LFS and told them what happened, they don't think the fish died but said that they like to hide in rockwork and is very likely the fish is just hiding, give it 2-3 more days to see if it comes out. They've heard of fish "disappearing" for 10-14 days before showing back up. Since it was swimming and eating on Saturday they feel that's what's going on here and I'm jumping the gun thinking this one died when I don't have a body to confirm it.

 

[CaptainAhab]

What's in ur cuc?

 

[smnw10]

Just snails right now, mostly dwarf ceriths and some larger florida ceriths.

 

[melosu58]

I personally think something was wrong with the dottyback. It was either stressed out by other fish or had a bacterial infection which was the real cause of the fins looking bad.

 

[smnw10]

I agree with that on the first one Mike, but at least that one I found a body and knew it had died. This second one though looked really healthy, vibrant color, swimming, eating, didn't look like it had difficulty breathing or anything...wasn't being picked on by the other tankmates...just suddenly disappeared.

Since it's all rock in the tank right now I'm tempted to go looking for it and pull all the rock out but I really don't want to disturb everything or run the risk of stressing the other fish. I just find it strange that a fish would vanish like this and the LFS says it's not out of the ordinary, I hope they're right. The next closest fish store is 4+ hours away...

 

[cmor1701d]

That's one of the reasons for a QT tank. You can see them and they can't hide in rock in a large tank.
Do you know if it was wild-caught or aquacultured? Aquacultured tend to be more hardy and they don't have the stress of being shipped half way across the world. Thes fish are swimmers and jumpers. I would not expect it to stay very long in a rock if there's food for it.

If it died the cuc might have taken care of it.

You might want to slow down on the fish additions to let the biological filter have a chance to catch up with the new bioload. Just add 1 or 2 at a time. I know they're small, but your tank is new and mostly base rock.

 

[smnw10]

Yea, I need to go a little slower, providing the same info to the LFS and they say it's no prob.
As for the QT, I even had everything except a heater ready for it but was too anxious to see more fish in the tank that I bypassed it...lesson learned.

I'm just a bit shocked that a healthy looking fish, swimming freely, eating readily one day, and just gone the next.

Thanks for the input everyone. Maybe the LFS is right and the fish will show back up, but I suspect not.

 

[Kurt_Nelson]

The LFS could be right... I've seen those things suck up into pockets on the underside of rock that surprised the heck out of me. Granted... they were trying to avoid a net, but unless you picked the rock up and turned it upside down, you just weren't going to see it. On the other hand... yeah - you'd think it'd come out for food.

You said there are 2 clowns in the tank. What kind are they?

 

[smnw10]

False Percula clowns, everyone had been nice to each other for the 36 hours or so I had them.

UPDATE:
mystery solved, I couldn't stand wondering what happened so I went looking and I found it but the dottyback unfortunately died, had gotten stuck in a rock. Anyone with Marco Rocks knows the kind of holes in them, well, there was a larger opening on one side that "snaked" through the rock getting smaller about as big around as the dottyback and came out the other side. The problem was the other side had an arch across the opening so the fish couldn't just swim through. It could get it's head through but then couldn't turn to get out (like wide prison bars that you can get your head through but not your shoulders). The fish was really tore up on the sides from apparently struggling to turn to get out. I couldn't even get the fish out without breaking that arch blocking the exit of the hole...
How sad. At least everything makes sense now.

So Dottyback #1 either got picked on at the LFS or has a bacterial infection that killed it, but I knew that risk when I bought it.
Dottyback #2 simply got stuck in the porous rock in a very unlikely scenerio where it could see an exit and fit through the exit but couldn't turn to get it's body out.

Rock is broken now so that won't happen again.