Small Tank.. two disappearing fish??

[saltyMJ]

In the past two months I've had two fish go missing from my 32 gallon cube. One carpenters flasher wrasse and one tail spot blenny. Both acting completely normal and very healthy up until they vanished. Blenny had been in there over a year and wrasse was about 6 months old. Both just vanished. I have a lid so I know they didn't jump out. Other tankmates include 2 oscellaris clowns, yellow clown goby, and a yellow watchman goby/pistol shrimp pair. And a peppermint shrimp. They both lived in the same rock, hiding in its holes at night time. Could they have gotten stuck? Or eaten by something? Any thoughts?

 

[Dan_P]

In the past two months I've had two fish go missing from my 32 gallon cube. One carpenters flasher wrasse and one tail spot blenny. Both acting completely normal and very healthy up until they vanished. Blenny had been in there over a year and wrasse was about 6 months old. Both just vanished. I have a lid so I know they didn't jump out. Other tankmates include 2 oscellaris clowns, yellow clown goby, and a yellow watchman goby/pistol shrimp pair. And a peppermint shrimp. They both lived in the same rock, hiding in its holes at night time. Could they have gotten stuck? Or eaten by something? Any thoughts?

Did you look for them at night after the lights were off?

 

[saltyMJ]

Did you look for them at night after the lights were off?

I have. I've checked in the mornings before the lights come on and at night after they go out and haven't seen them. They are surely dead at this point. Just trying to figure out what is killing them so it doesn't happen to any others!

 

[saltyMJ]

A third fish has disappeared.. I have a tight fitting lid with no gaps so I know they aren't jumping. I'm thinking I have some kind of unknown pest hiding in my rockwork that has recently started preying on my fish?? Anyone know what it could be? And any possible solutions? This is three healthy fish gone in about 2 months. No remains discovered anywhere. Could it be the pistol shrimp??

 

[Reeferoni123]

Crabs and worms could be culprits - try leaving some bait out after lights out and watching with a dim red light only. See if any monsters show themselves…

 

[Fish Fan]

Where did your rock come from, was it wet, live rock, or dry rocks? Sometimes with real wet rocks you can get a pest like a Mantis or Gorilla crab that could be largely unseen, but getting the fish.

After that, I'd say some kind of disease.

 

[saltyMJ]

Crabs and worms could be culprits - try leaving some bait out after lights out and watching with a dim red light only. See if any monsters show themselves…

Thank you for the advice. I will give that a try tonight

 

[saltyMJ]

Where did your rock come from, was it wet, live rock, or dry rocks? Sometimes with real wet rocks you can get a pest like a Mantis or Gorilla crab that could be largely unseen, but getting the fish.

After that, I'd say some kind of disease.

Live rock from that fish place in Lancaster Pa. I've had the rocks in there since the start of the tank, almost 3 years now. And this just recently started happening.

 

[Fish Fan]

What was the last livestock you added? If you're sure you don't have a pest like a Mantis, then this would almost certainly be a disease issue.

 

[Dom]

What was the last livestock you added? If you're sure you don't have a pest like a Mantis, then this would almost certainly be a disease issue.

For them to disappear so completely and suddenly leads me to believe it is a predator of some kind.

 

[SomeHappyFish]

Do you have a lid ?

 

[Uncle99]

Systematic death…..Same here, turned out to be mantis…..green and 5”.

Got him though, no to smart, not to fast.

 

[SomeHappyFish]

I would check behind the cabinet..

 

[Fish Fan]

For them to disappear so completely and suddenly leads me to believe it is a predator of some kind.

That was my first thought too.

 

[saltyMJ]

What was the last livestock you added? If you're sure you don't have a pest like a Mantis, then this would almost certainly be a disease issue.

We hadn't added anything in over 6 months. Then we lost two fish within a few weeks of each other. We let a couple weeks pass by and then just last weekend we bought two new ones to add in. They both seemed to be acclimating well and getting along with the other inhabitants. Then out of nowhere i noticed the new kamora blenny is missing and no where to be found. We don't know of any known pests but my wife did just remind me that we added an emerald crab a long time ago, about a year. We stopped seeing him eventually and assumed he died, thought he fell prey to the pistol shrimp. But maybe he is still alive and grown bigger? I don't think it is disease because all other fish seem to be fine and doing their normal things...?

 

[Fish Fan]

We hadn't added anything in over 6 months. Then we lost two fish within a few weeks of each other. We let a couple weeks pass by and then just last weekend we bought two new ones to add in. They both seemed to be acclimating well and getting along with the other inhabitants. Then out of nowhere i noticed the new kamora blenny is missing and no where to be found. We don't know of any known pests but my wife did just remind me that we added an emerald crab a long time ago, about a year. We stopped seeing him eventually and assumed he died, thought he fell prey to the pistol shrimp. But maybe he is still alive and grown bigger? I don't think it is disease because all other fish seem to be fine and doing their normal things...?

Geez, not really sure then. I don't know what else randomly takes out fish other than disease or a predator. Emerald crabs can be problematic, but I would think if yours got big enough to be taking down fish, you'd see him from time to time. Gorilla crabs are more likely to take fish, and they hide all day, coming out typically after the lights are off. In fact, if you haven't yet, check the tank after the lights have been off, use a flashlight, and maybe you'll find the culprit here.

 

[saltyMJ]

Do you have a lid ?

Yes, glass lid and also have netting in the corners near the filters and stuff. We lost one that jumped out early on in the hobby and made sure it wouldn't happen again!

 

[saltyMJ]

I would check behind the cabinet..

Oh we did!

 

[saltyMJ]

Systematic death…..Same here, turned out to be mantis…..green and 5”.

Got him though, no to smart, not to fast.

Interesting. How long was he able to go in your tank unnoticed for?? And how big is your tank?

 

[Tahoe61]

No Serpent Stars?