on the killing of hitchhikers...

[rhenson]

I am not having any luck capturing a large mantis shrimp and a large gorilla crab. I know I have a lot of other good hitchhikers. I was wondering about treating the tank with a copper product to just kill off all of them off and then replacing all the good snails and crabs. I know this probably is a bad idea – but, despite the “killing” aspect of it – is this a sound idea – would it only kill of my crustations or would stars, corals or other aspects of the tank be impacted?

[patsan]

OMG DON'T DO IT!!
You'll kill all the rock too!

[rhenson]

Funny...well, it was an idea. The other idea I've had thrown at me is to get a trigger fish and let him get rid of everything, but surly this would affect corals....does anyone have any ideas...Or is the real only solution to keep setting traps in the tank inthe hopes that some day I'll get lucky?

[patsan]

Is there any possible way you can take the rock out of the tank to try and remove the mantis? That would be your best bet....if you can do it.
Can you reach in and grab the gorilla? I personally can't touch the crabs, but many people have said they removed them by reaching in and just grabbing them.

[Jocko]

I'm by no means an expert but I've seen it said many times that basically once you've introduced copper it will always be present. It will be in the rocks and sand and seep out and always kill things. It's really not an option. Of course I'm not speaking from experience, just repeating things I've read.

What have you tried so far? I didn't have much luck with the standard water bottle home made trap, but managed to catch 3 gorillas using a shot glass! I just put some food in the bottom and leaned it up against the rock. It didn't take long for the hungry/curious gorillas to start climbing around and eventually they fell in. It was too slippery to get out. Hehe. Obviously this would only work for smaller guys.

I think alot of people eventually just took out the rock that the mantis lives in and then shot some soda water in his hole until he popped out. Have you tried that?

[mikedsokc]

I bought a used tank several years ago that was still setup. It was a fish only tank, so I didn't thank anything about it at the time. I bought a starfish and put in the tank and it started to disintegrate after a few days. I had the water tested and it had large amounts of copper in it. It took me months to remove the copper. I had to replace all of the sand and rock. After that still did not remove all of the copper, I had to use some filter pads that I don't remember the name of. In short, I would never use copper in my tank on purpose. I hope this helped.

[Slicktrax]

i will second the soda water trick. pull the rock, place it in a shallow dish and squirt the soda water into the hole where the mantis is hiding. i caught and removed 5 mantis this way. it will also cause anything else in the hole to leave.

[steve9k]

I've had a reasonable amount of success by grabbing the crabs with a pair of tweezers whenever I spot them. Sometimes all I get is a leg, but I've grabbed about 4 this way, and I think I've only got 2 to go. But I'm certainly going to try the shotglass approach -- sounds too easy.

[sandlot13]

hey, if you catch that mantis shrimp, send him my way!!! ill pay for shipping!!!!

[Splach]

I had a great deal of success getting rid of gorillas by taking a 1/4" rod of stainless steel, sharpening it to a spear on a grinder and baiting it with a piece of silverside (lengthwise so it wont come off). Waive it over the hole they are in (during feeding works well since the smell is in the water). Wait until they are right underneath it and "WHAM". Unfortunately even with a spear through them they will hold onto the rocks. If you can leave a few burs on the rod to hold on while you try to lift them loose of the rock.

[rhenson]

sandlot - if he lives through it, I'll get in touch with you...but with splach's idea there...I'm not sure he will. Spear him...sweet.

[vermonter310]

This worked slick for me.

http://reefcentral.com/gallery/showphoto.php?photo=136684

[Splach]

Actually I never managed to spear a mantis. They are just too @#*@ fast. I got mine out with the seltzer trick (in fact if you go back far enough I think I was the first to post it, but I could be wrong). It definetly works. I was in my pantry thinking hmmm what could I put on the rock that wont screw up my tank... Hmmm carbonated filtered water... That shouldn't be too bad... First mantis I hit with it literally FLEW a foot out of his hole. The second one was a bear and let it kill him in there (didn't take much, carbonated water is apparently very harsh on these guys) then I had to dig him out though.

My last mantis I got out live (I have a post on the mantis forum looking for a home for him) and I got him out by sheer luck.

[CTS]

Why are these things so bad for a tank?

[rhenson]

For me they have eaten most of my cleanup crew, which I will have to replace. Looks like sandlot13 has a "mantis shrine" I would love to see a picture of that...he's sick!

see: http://www.tbsaltwater.com/thepackage/watchout.html

"...Mantis Shrip are one of the most colorful and interesting of all the "characters" of the reef. BUT, its diet consists of crustaceans, worms, fish and even mollusks, smashing their shells open with its powerful front claws..."

[sandlot13]

hahaha, yes i do have a mantis shrine (for my mantis J.R., or Jack the Ripper) ;) these guys are awesome! clever little buggers!

[rhenson]

They are very clever - I'd set a trap and he would observer it from several spots around the tank and if he could figure it out, he'll get the bait - otherwise, genearlly speaking, he stayed away! It has been fun trying to catch him. I got home from work today and my wife was jumping up and down - she had caught him - I tried and tried - but she got it done. I was telling her about your shrine sandlot...and it sounds like we will be joining the ranks of mantis shrine owners. I'll make a post early next week about the technique she used...it was a good one.

[sandlot13]

congrats!!! good luck with everything, let me know how it goes!!!

[goblinsharkman]

Originally posted by CTS
Why are these things so bad for a tank?

Mantis shrimp are one of the most interesting creatures one can keep in an aquarium, they are extremely smart and very amusing. They are also one of the most evolutionary advanced crustaceans, they the most advanced eyesight of any animal (over 100000 colors (humans only see 10000) and detect polarized and ultraviolet light) and they have the fastest moving appendages of any animal. Some people have problems with them in small reefs or if there are multiple shrimps, but if they are in a 120+ tank they will do little damage. If at all possible i would suggest cathing them alive and keeping them in a seperate 2.5-10 gallon aquarium. Theyre a lot more fun then pistol shrimp! :)

[kp1917]

Use the tool that vermonter310 shows in his post. I used that a couple of years ago when I first got my shipments and it works great. I got rid of three mantis and a few gorilla's and only missed once and the mantis came right back after it and WHAM.

[snookhunter]

If you have a separate tank suspend the rock above the floor of the tank...say on an egg crate shelf with pvc pipe suppors/legs or pvc pipe rack. Then place a meaty bait on the bottom of the tank. The crabs and shrimp will smell the bait, come down to eat it and not be able to climb back up into the rock. The free for the taking.

I haven't tried this but read about it. Worth a try...

[miztic]

<a href=showthread.php?s=&postid=6199779#post6199779 target=_blank>Originally posted</a> by snookhunter
If you have a separate tank suspend the rock above the floor of the tank...say on an egg crate shelf with pvc pipe suppors/legs or pvc pipe rack. Then place a meaty bait on the bottom of the tank. The crabs and shrimp will smell the bait, come down to eat it and not be able to climb back up into the rock. The free for the taking.

I haven't tried this but read about it. Worth a try...

Should work ok on crabs, but the mantis can swim back up :)

[ladyshark]

I lucked out--only had two mantis, but a bunch of gorillas. Happliy, the mantis eventually ate the gorillas, and I got one of the mantis out by grabbing his rock home and plopping it (and the mantis inside) into a 3 gallon Eclipse system with some southdown and a yellowtail damsel, where they both live today eating only when I feed them. Amazingly, the damsel continues to survive.

The other mantis continues to terrorize the reef tank, and cause my snail population to dwindle and need replacing from time to time. He is clever, but I will get him eventually.....he even killed and gutted my beloved "Biff" -- a large red mithrax crab---the only thing left was a hollowed out shell, legs intact. Very sad.....