So there HAS to be a mantis in my main tank


Reefing newb
Right now I have a 30gal that just some live rock in it, no clue what to do with it yet.
A 70gal mixed reef/fish
and a 30gal tank with a peacock mantis shrimp

In the 70, over the past 2 months, I have kept hearing a clicking sound from this one large rock in the corner. Sometimes I'll hear it once, then sometimes I'll hear it 6-7 times in a row. It's not the peacock mantis shrimp in the neighboring tank, I've had my face up against the glass and heard it straight from the rock.

So today I heard it 7 times in a row, loud, and I was in my chair checking the tank out, and I'm convinced that there HAS to be a mantis shrimp in that rock. I dunno what else it can be. I also can see 2 snail shells that have been shoved under the rock in a little burrow, and an indent in the sand where something has moved the sand. Don't think its my diamond watchmen goby, he can't go under the rock like that.

I've never physically SEEN it, although I've tried many times.

So what are some inexpensive ways to draw him out or maybe even try to catch him?
If it turns out being a mantis, and I can get him, he will go into my extra 30gal tank and I'll start building a home for him there. I love these guys.

What do you guys think?
Yup, sounds like a mantis or pistol shrimp. You're lucky you haven't been losing fish or cuc to it yet! I'd check in with Dana - he's caught them before and might have some ideas. Sounds to me like you already have a tank ready and waiting for it :)
I would say its a pistol I have had one in my tank since I first set it up. I have tried to kill it by dipping the rock in cold water, hot water, freshwater, no water,

NOTHING has worked lol.

I used to have my tank in my bedroom but it drove me to instanity so now its in the office and he still pops away while my 50 fish die off. Go figure
agreed, it's most likely a pistol shrimp. The mantis shrimp don't do multiple quick snaps together.
Well thankfully, I love mantis shrimps and I actually stay in contact with Roy Caldwell over in Berkeley, California. He's the man when it comes to mantis shrimps!

I've never had experience with pistol shrimps, and I don't think that they would make this sound repeatedly 7 in a row

He has to be small, like very small for him to be in the rock that he's in..But he still has to have some size to him to make the little clicks with his hammers.

I did actually dip the rocks in freshwater before I put them in to get a lot of the critters off. Never know what you can have. Now the rock is covered in expensive zoas.

I'm not ruling the idea of a pistol shrimp out YET, but thats because I've never met whatever this is before, just heard it.

When it comes to catching him, I don't really want to have to spend a bunch of money on something, and I don't want to mess with the rock either. These gets can be very tricky and clever sometimes\

EDIT/ After watching some pistol shrimps on youtube, and the sound it makes, I am leaning towards pistol shrimp for the sound..But still waiting on the day that I see him
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Next time you feed you could try to dangle some food on a stick near the rock (and cave entrance that you described) and see if he'll come out to grab the food.
Yea, I was thinking about doing that Fishy. That's how I feed my peacock mantis.

But I don't know a lot about pistol shrimps and their behavior so I don't know what I can do to get him out.
I honestly wouldn't worry about it too much. My pistol is more than capable (size-wise) of taking my clowns down and hasn't ever tried anything.
i thought i had a pistol shrimp in my tank, kept hearing clicking, every now and then, sometimes 5or 6 in a row, so sat there one night with a torch only to find out it was one of my turbo snail getting stuck behind the rock and the way it was moving he kept tapping the glass, i also had a hermit doing the same, trying to get through a narrow gap between glass and rock, tap, tap, tap, mystery solved!
Oh well. I hear the clicking in 2 different spots now, but more frequently in the same rock in the corner.

I guess I won't worry about it until I actually see whatever it is
So tonight I'm going to set out some water bottle traps just for the hell of it.
Whats the best thing to bait these guys with?
Yea. I didn't have any luck either. I know he's there, and I believe I found his little cave, but I caught nothing but crabs and peppermint shrimp