Using a mantis for good?

Herbert T. Kornfeld · #1 08/17/2004, 12:06 AM

Just an idea, but I thought I would post it here in case anyone sees a problem with it. I have a friend who bought some LR from the LFS via a fresh shippment. Turns out it is covered with nasty little gorilla crabs and such....NOT REEF SAFE ONES. We were kinda shocked when we looked at the tank after a few days of curing and saw the resident crab families. Now, we could try to pick them off...and maybe get them all...but since were going to let the tank sit for 6 months before adding anything else...and there is about 150lbs in there of cave infested rock (otherwise very good looking rock)...it dawned on me...put a mantis in there and let it take care of all the crabs...and when it's done...just trap the mantis. Sounds good...right? Anyoe have experiences trapping larger mantis? I am thinking we will grab a 6" peacock that I saw at another LFS has for $30.

Jeremy Blaze · #2 08/17/2004, 09:32 AM

Sounds like a plan! Might be tough catchging the mantis, but I'm sure it would be easier than catching all the crabs!

Dwayne · #3 08/17/2004, 12:54 PM

Interesting scenario. I would 'test' the mantis with a crab in a small tank before dumping the mantis in the main tank. You wouldn't want to have two 'trouble makers' in the main tank.

Herbert T. Kornfeld · #4 08/17/2004, 08:15 PM

test? how so do you mean? It is a peacock...so it would be a smasher...the rest should good...but please tell me what you have in mind, after all, that is why I posted the idea here.

Tballa · #5 08/17/2004, 08:18 PM

it should work. It won't be hard to catch it either. I mine its 6" not like 2. Great idea!

Dwayne · #6 08/17/2004, 09:38 PM

Quote:

Originally posted by Herbert T. Kornfeld
test? how so do you mean?

Put the mantis and an unwanted crab in the same tank. Just to make sure the mantis finds your unwanted crabs to be appealing. It wouldn't be too kewl to put the mantis in the tank to find out the mantis has no interest in your unwanted crabs.

Herbert T. Kornfeld · #7 08/18/2004, 11:40 AM

oh, yeah, i read you...but the mantis is kinda big, so if I have to catch him in the main tank it shouldnt be to hard.

theseeker · #8 08/18/2004, 06:00 PM

Do you mean an emerald green crab? If so they are reef safe.
Unless you have experience catching a mantis that is fool proof you are inviting ants to the picnic. The only way I have disposed of a mantis was by pure luck, he molted and my two sallylightfoots ate him!
A question for you-why would you let the tank set for six months?
Three to four weeks, a nitrogen cycle and then do a 100% water change, add your cleaners, wait two weeks, turn on the lights and your ready to add livestock. It worked for me.

Herbert T. Kornfeld · #9 08/18/2004, 11:29 PM

They are not emeralds...they are gorilla crab looking. Like emeralds, but black and brown. Nasty SOBs. They tore up the green chromis trio he had in there to help the cycle. It isnt that we wont be doing anything for the next 6 months...but not getting to the really good stuff/ final plans until then. Over the 6 months we will monitor the water, add in some disposable corals like GSP, xenia, shrooms, etc. But the tank is destined to be a clam / sps tank...so were going to take our time. The tank is also going to be a mud based filtration (not to worry, a decent skimmer as well) setup for plankton that we will spent the next few months getting broken in and inhabited.

archmage · #10 08/20/2004, 07:37 PM

Herbert,

Unless your main display tank is empty of rock, it would be a PITA to get the mantis shrimp out. I spent over three weeks to get mine out and it was by pure luck. He went over the overflow. The gorilla crabs on the other hand, are very easy to catch. Just bait a small cup with a line and when the crab goes in, just lift the cup to a vertical position. I've caught two crabs within two days of baiting and they acknowledge the bait within two hours of baiting. The shrimp just ignored my bait. If you plan to keep on replenishing your snails, I wouldn't put one in the main display.\

Just my opinion.

NwG · #11 08/21/2004, 03:15 AM

Sound like fun be sure to make a video!!!!!

biomekanic · #12 08/21/2004, 12:32 PM

Quote:

Originally posted by theseeker
Do you mean an emerald green crab? If so they are reef safe.
Unless you have experience catching a mantis that is fool proof you are inviting ants to the picnic. The only way I have disposed of a mantis was by pure luck, he molted and my two sallylightfoots ate him!
A question for you-why would you let the tank set for six months?
Three to four weeks, a nitrogen cycle and then do a 100% water change, add your cleaners, wait two weeks, turn on the lights and your ready to add livestock. It worked for me.

There's a lot of life that arrives on LR in bad shape, and a lot that is found as eggs/spores. If you allow the LR time to recover from the shipping/curing process by not introducing predators (such as fish and corals) and getting animals such as the gorilla crabs out, you can have some spectacular looking rock. I've seen tanks done like this, and they look really good. It also allows the pod population to expand to the point where it's more self-sustaining.
SOP in Europe is to wait six months to a year before adding anything to the tank other than a clean up crew. I've seen the pictures of the results, and that's my plan for my next system.

As for the mantis... fishing out a 6" peacock is a lot different than fishing out a 2" little smasher. It's world's easier. It took me over a month to fish out the little one I found in my main tank, and 1/2 an hour to catch the big one I had in her own display. All I had to due was lure her out with some food and scoop her up. If you go with the mantis plan, I'd recommend supplemental feedings with the krill soaked in selcon (or anything similar) and little garlic juice (mine loved the smell), that way it'll learn to associate you with food, makes capture much, much easier.

Ryan · #13 08/21/2004, 04:54 PM

a trigger would be easier to catch and return

Herbert T. Kornfeld · #14 08/21/2004, 10:56 PM

hmmmm. thats true...perhaps some types of fish would be a better idea...like a small grouper...hawkfish, or predatory wrasse...hmmmm....

cephalopoder · #15 08/22/2004, 05:11 PM

How about a octopus! You can get a nice O.mercatoris pygmy octopus from a florida vender and it will be able to get inside all the nooks a larger mantis can not. The short life span of pygmy octopuses <1 year would make getting rid of the octopus easy because most that are collected are adults all ready and have less than 6 months to live.
You just have to make sure your tank is cycled so your ammonia and nitrite levels are zero. O.mercatoris is a hardy little octopus and many have been found in peoples shipments of TBS live rock. Pygmies are also nocturnal so they will be out hunting while the crabs are out feeding as well. You can ask TBS if they can locate you one. I have been told octopuses are sold in europe for this specific problem.
My 2 cents.
chris

tidesntails · #16 08/23/2004, 05:03 AM

i would go with an octpus also as long as you can seal the tank up they are whodinnie(?spelling).
good liuck with hatever you decide to do.

Devious Rhesus · #17 08/23/2004, 09:59 AM

You could also put a collar and leash on the mantis while you're at it...

Aquatect · #18 08/28/2004, 02:29 PM

Haha

Well you could also use a crab pot now couldnt you?

An octopus is getting a little extreme now isnt it? Not to mention the fact that if you think getting a mantis out is hard, imagin getting the octo out... The only way I've ever been able to do it (We had a vulgaris that layed eggs at work and they ALL escaped into the system cuz they were so small) is to lure them out, keep them distracted and net them if theyre running free. You could try a sealed crab-in-a-glass-jar for octo bait cuz he'll be working on opening it for a while.

I dunno... The best thing I can think of is that you've got 6 months to wait, just pick out the crabs by hand... it's not like youve got a 2 week deadline to meet.

cephalopoder · #19 08/28/2004, 04:38 PM

Quote:

An octopus is getting a little extreme now isnt it?

No, actually I don't. If you read my post I covers all the aspects of why you would not have to collect the octopus from the tank.
O.mercatoris in a tiny octopus that is only a threat to small crabs and crustaceans. It is not a monster like O.vulgaris that lives allot longer and grows to a rather large size.
As for O.vulgaris laying eggs in your system I am not sure how that is relevant to any thing. O,vulgaris is a small egg species that hatch into planktonic young that can not be reared unless you have a kreisel and they would naturally all get suck into the overflows just like a tank of artemia would. I have kept dozens and dozens of cephalopods. I have breed O.bimaculoides and reared he eggs from hatching to adult and I have also reared O.mercatoris from egg to adult. Some of my pics of the breeding and the hatchlings are in the gallery.
Don't be so harsh just because its a idea that involves thinking outside the box. If I listened to every body that tried to discourage me when I set out years ago to breed octopus, I might not have succeeded and been unable to share what I have learned with every one else.
It is doing new and different things that keeps this hobby interesting.

Herbert T. Kornfeld · #20 08/28/2004, 07:55 PM

Aquatect, well...the whole point is that we dont want to have to keep on putting our hands in the tank. The crabs are quite hard to keep track of. Between their reaction speed and the cloudiness of their tank right now...i would rather not. The idea is to le nature take it's course and just sit back.

Aquatect · #21 08/29/2004, 12:00 AM

yea, my bad on calling it a vulgaris, we ordered what we thought was a vulgaris but clearly it wasnt after laying eggs... My bad on that one. I'm not being harsh, it just seems like there are other ways of doing it. Just because someone offers an opinion you dont like doesnt mean its wrong and you need to flaunt your ceph. credentials to prove it. Which, by the way... If I listened to everyone who didnt like my opinion i wouldnt know so much either

Shoestring Reefer · #22 08/31/2004, 03:31 PM

Just make sure the mantis (or octopus) isn't about to lay eggs. Or you'll have to send in something REALLY nasty.

Aquatect · #23 08/31/2004, 09:51 PM

If the mantis goes egg rampant that doesnt leave much besides an octopus. If the octo goes egg rampant... well... better find a bigger octopus, haha

cephalopoder · #24 08/31/2004, 10:25 PM

I wouldn't worry to much about the mantis laying eggs and having a army of little killing machines in your tank. Stomatopods hatch into plank tonic larvae and can not be reared easily even under the most controlled conditions with special rearing chambers and select live food. They are also cannibalistic at birth and the largest of the hatch would soon eat all the smaller siblings should by some act of god they even survive that long in the system.
If a pygmy octopus laid eggs the odds are again slim that any would survive on their own due to their size at birth and food requirements. But hay, if by a miracle in either scenario some did survive you would have something to be very proud of and could easily sell or find homes for in the stomatopod or ceph forums.
Aquatect I guess I did flaunt a little in my last post and maybe came down a little harsh on you as well. In trying to point out that I had some knowledge of what I was talking about, I guess I over did it a little. I apologize for coming across as flaunting .

Shoestring Reefer · #25 09/01/2004, 09:57 AM

Okie Dokie.