Tank Killer, any suggestions?

[dantodd]

I had 4 chromis disappear over the course of a week about 4 years ago. They were all brand new to the tank.

I never had another fish disappear since so I didn't think much about it. I figured maybe they had each found a different (or the same) hiding place and then died there.

Well, I am pretty sure there is something lurking in my tank and has been there for many years. I put a 4" yellow head sleeper goby in the tank and he disappeared on the first night in the tank. I am not pretty certain someone is in my tank and it eats well. I made a crab/shrimp trap out of a half litre coke bottle tonight and we'll see if anything happens tonight. I have a feeling whatever can eat a 4" sleeper may not fit into my little trap. I recently put a small-mid sized crab in my mantis tank and he didn't even look at it again so I doubt that I can put in whatever is killing my fish, might be too much.

I am certain it isn't a smasher mantis or pistol shrimp as I've never heard anything resembling the sounds they make. I suppose it could be either a nasty crab or possibly a spearer mantisbut I doubt the mantis would have survived that long without another fish.

[andiruleu]

gobies tend to jump out of new tanks.. do you have covered top? if not.. check around the tank to see if the goby is on the floor .

[dantodd]

nope, not on the floor. The floor is pretty uncluttered and I'd see him for sure.

[akrimmel]

could be gremlins

[fish are life]

i have had fish dissapear many times but i figured the cleaning crew just took care of it

[Rockfish]

My Yellow Watchman disappeared when initially put in the tank then resurfaced two weeks later after I had given up on him. That was 1 1/2 years ago, then 2 months ago he disappeared, he resurfaced yesterday. If your tank has lots of rock and sand and they find a burrow and it's off the beaten path you may not see him all the time.

[reefgeek84]

I assume you have live rock...could be a mantis shrimp.

[dantodd]

if it's a mantis he's a spearer since there is no smashing sounds. I have a mantis in my other tank so I'm quite familiar with them.

As for hiding, I guess (and hope) that could be the case. I'll keep holding out hope. He's pretty big and spent his first day sifting sand constantly so it's hard to imagine but I really hope he's just hiding.

[RichConley]

<a href=showthread.php?s=&postid=7340391#post7340391 target=_blank>Originally posted</a> by dantodd
if it's a mantis he's a spearer since there is no smashing sounds. I have a mantis in my other tank so I'm quite familiar with them.


Spearers live on mudflats, not in live rock, so its almost impossible to get one by mistake in a live rock shipment.

[v8maro]

What kind of sound does a mantis shrimp make?

[dantodd]

usualy clicking noises, very much like a pistol shrimp. They make the sound when digging out caves in the live rock and when opening shells.

[v8maro]

Well I have this loud click that comes from my tank every so often, but nothing has been killed (that I know of). How would I get rid of this thing? It's pretty loud too. I always just thought it was my trigger fish doing it? Guess not? Are these shrimp bad??

[v8maro]

Well I have this loud click that comes from my tank every so often, but nothing has been killed (that I know of). How would I get rid of this thing? It's pretty loud too. I always just thought it was my trigger fish doing it? Guess not? Are these shrimp bad??

[dantodd]

as long as they aren't killing anything they aren't bad at all. If it is a mantis you will likely find some of your snails/hermits missing. The sound you hear with mantis is them using their "smasher" or dactyl to make caverns in the live rock. If it is a pistol shrimp the noise you hear is him clicking his claw which sends out a strong sound wave which they use to stun their prey.

For either animal you can create a shrimp trap to try and capture them.

Cut the top off of a plastic soda bottle and then turn the top around so that it is like a funnel going in. Drop in a piece of thawed, raw table shrimp in the bottle and whatever it is will almost certainly go in.

[dcombs44]

I have a disappearing issure, except with corals. I had a ricordia frag that was growing and doing well disappear one night as well as the tentacles from my green button polyps. The only fish i have in my tank are a yellow tang and a tomato clown. Inverts are harmless too...just some hermits and some margarita snails and fire shrimp. Once in a while i will see some sort of creature shoot across the bottom of my tank. It's black without a shell, but that's all i can catch. very fast and i only ever see it for an instant. and now that someone mentions it, i do hear a click coming from my tank once in a while. Could this creature be the source of my problems, or something else?

[dantodd]

el chupacabre?

[dantodd]

in all seriousness though, if you know about where it is in the tank (at least where it runs) you can try and set a trap.

[dcombs44]

haha....actually, every time i've seen it it's been in a different place. The sand, up in the rock, etc. etc. etc. I've went flashlight searching at night also and no luck. But do you think it could be something that would munch on coral?

[dantodd]

no idea what eats coral, other than angels of course.

[dcombs44]

http://i5.photobucket.com/albums/y182/olivia640/Mantis2.jpg

Found this pic in the mantis forum...it's very possible that this is my mystery character, but that doesn't explain the coral...

What are the pros and cons of a mantis shrimp?

[dantodd]

great critters, amazing speed in attack and some of the most advanced vision systems in the animal kingdom.

They are predators. Smashers eat crustaceans and spearers eat fish. The smashers can empty your tank of hermits and snails.

Check out "Roy's List" the URL is in a sticky on top of the mantis forum. There are a lot of different very cool species. Mine is in his own tank area so I can keep an eye on him and better feed him directly. They are also full of personality in many ways.

[Amphiprion]

I second the gremlins.

Anyway, search for a stone or gorilla crab. They are even more secretive than mantis shrimp, in that they can even camouflage themselves with rock, etc. I had one years ago that had a "trap door", which it would open and shut to snatch certain things. You would never notice it unless it opened. That is just a guess, but be aware that it could be a potential problem.

[dantodd]

whatever it is he's old and he's still dangerous... He is also avoiding my trap...

[dcombs44]

http://www.ucmp.berkeley.edu/arthropoda/crustacea/malacostraca/eumalacostraca/royslist/images/g_falcatus2sm.jpg

If i had to guess...this is it...Gonodactylaceus falcatus

and again....now that you mention it...my snail and hermit population has slowly dwindled...

[dcombs44]

There are a few other possible matches on the list, but it looks something like the one above

[dantodd]

I'd build a trap and then set up a nice little 10g for him. Or set up your sump for him. They are great fun.

[dcombs44]

what would involve "setting up" a sump....my sump now has a center fuge area with miracle mud, a piece of live rock, calupera, and all kinds of pods and bristlworms and a sofshell snail that i don't think would last long with a mantis

[v8maro]

<a href=showthread.php?s=&postid=7356833#post7356833 target=_blank>Originally posted</a> by dantodd
as long as they aren't killing anything they aren't bad at all. If it is a mantis you will likely find some of your snails/hermits missing. The sound you hear with mantis is them using their "smasher" or dactyl to make caverns in the live rock. If it is a pistol shrimp the noise you hear is him clicking his claw which sends out a strong sound wave which they use to stun their prey.

For either animal you can create a shrimp trap to try and capture them.

Cut the top off of a plastic soda bottle and then turn the top around so that it is like a funnel going in. Drop in a piece of thawed, raw table shrimp in the bottle and whatever it is will almost certainly go in.

Like a 20oz bottle? Also, do i set it sideways? How do I secure the top to the bottle after i cut it off?

[dantodd]

I suspect the softshell snail would be dust pretty quickly but otherwise it sounds like a very nice home for a mantis. Depending upon the species they usually dig a burrow out of the live rock or will build one with live rock rubble/sand.

Best thing to do is capture him and then you can post a pic over on the mantis forum and they'll ID him and help you determine his requirements.

A for the soda bottle, a 20oz is great and usually you can just slip the 2 halves together they usually fit plenty tight enough.

[dcombs44]

So let me get this straight....i cut the top off of a 20 oz bottle...stick the skinny end in the sand with some bait, and he will go in and not get back out?

[v8maro]

no you have to take that top u cut off and put it back into the lower half except the 'mouth' is facing the bottom now

like so:

|\_/|
|__|

Can we just stick it in the sand??

[dantodd]

OK, you cut the top off of a 20oz bottle so that you have a funnel shaped top and a cylinder haped bottom. Shove the funnel shaped end down into the bottom so that the edges make a fiarly tight seal. It should look like a funnel leading into the bottle. If you put bait in the bottle the funnel will guide the shrimp in but it will be very difficult for it to get out because the hole is much smaller.

Here is a picture with a more elaborate design from tampabaysaltwater.com

http://www.tampabaysaltwater.com/thepackage/images/trap.gif