Mantis Shrimp

highflight

New member
I have an established, fish only, 90 gallon tank which is populated with 4 damsels, 4 clowns, 2 tangs and some cleaner shrimp, crabs, and snails. I am excited about ordering a package of live rock after seeing some of the pictures and descriptions in this forum. My big concern is "unwanted" hitchhickers, mainly, Mantis Shrimp...based on what I've been reading. If I were to get about 100 lbs. of LR, what are the chances there would be any mantis shrimp included? how hard would they be to remove from my tank before doing any damage? and what would be the best way to ensure they aren't introduced into the tank in the first place? What sort of gloves do/should you wear while handling the rock to prevent injuries?

Also, if the tank is well established with a Remora skimmer, Fluval canister filter and a large AquaClear....what are the chances I would have a dangerous spike in ammonia or nitrite? or would the biological filter and LR be able to keep up with it fairly well?

Thanks...I'm sure I'll have more questions for you....but looking forward to getting started once I educate myself somemore.
 
I think you'll find it varies. I just got part 1 of a 75 gal package. I found 1 mantis and 1 stone crab. I've read posts where some one got no mantis but alot of gorilla crabs.

Right now I don't know if I missed finding any other unwanted hitchikers.
 
About 300lbs in so far, I have at least three mantis and at least 50 gorilla crabs.

The mantis are staying in the tank...the crabs I'm less sure about.

Crabs are easy to catch using a tilted glass with bait at the bottom. Put the rock in the tank and catch them later.

Mantis are more difficult to get once they are in the tank. It is my experience that any sudden change of water causes them to hastily exit their hiding spot for just a moment. Repeated plunging into a bucket of tank water often makes them try to escape (into the bucket!) Since you are dipping into tank water, I expect that harm to the rocks other residence might be minimal (bound to be hard on sponges, though)

Once you get the mantis make sure you find a home for it. There are lots of people who want them.
 
<<< If I were to get about 100 lbs. of LR, what are the chances there would be any mantis shrimp included? >>>

Impossible to say for sure, but odds are you may get 1-2 or more with 100 lbs. of rock.




<<< how hard would they be to remove from my tank before doing any damage? >>>

I think (from experience) the best way is to flush them out of the rock before it goes in your tank. The best way I and others have found is to use a large syringe or turkey baster filled with cold carbonated freshwater and quickly shoot it into their hole in the rock and they typically come flying out of their hiding place, although some are more persistent then others and may take a few good squirts. I wouldn't advise dipping the entire rock in freshwater as this could easily do harm to other life on the rocks. This method is far easier and less stressful then trying to remove them after the rocks are already in your tank, as traps typically don't work too well on them in my experiences.




<<< What sort of gloves do/should you wear while handling the rock to prevent injuries? >>>

Coralife Aquagloves work great....about 15.00





<<< Also, if the tank is well established with a Remora skimmer, Fluval canister filter and a large AquaClear....what are the chances I would have a dangerous spike in ammonia or nitrite? or would the biological filter and LR be able to keep up with it fairly well? >>>

It depends.....that skimmer is already just marginal for a well stocked 90g. w/fish and you may get a small amm. spike but probably nothing serious. Dosing Seachem Stability daily for several days may also help after adding all the new rock. Check the rock for any dead/dying sponges as they would be the most likely cause for an amm. spike after adding the new rock.
 
In our first half of rock, 120 lbs., we got 4 mantis shrimp a bunch of gorilla crabs, an octopus with eggs and 5 pistol shrimp. Three of the 4 mantis shrimp were relatively easy to get out of the rock by shooting either fresh or cold carbonated water into the holes but the fourth one we are still fighting. We've taken every rock out of the tank and shot all kinds of water through all of the holes.

We've decided that the second batch of rock doesn't go in the tank until we've injected the holes with water. BTW, this really helped to get out the crabs too.

Our plans are to first swish each new rock in the salt water that we've removed from our tank then we are going to put the rock in another tub and squirt the holes. It's really a pain to try to remove a mantis from an aquarium. They have unbelievable eye sight and move lightning fast.
 
What sort of cold, carbonated water should I use? Would this be like seltzer water? tonic water? Perrier?

I think I might put my fish into another aquarium and then inspect/squirt the rock in some tubs before putting it into a non-populated aquarium. Hopefully I'll be able to get them all.

Are there any other precautions to take when flushing the holes of the rock?

Any guess as to how long after the rock is in the tank before you'd know if you missed a shrimp? Are the sounds that obvious? I've never experienced it.

What about pistol shrimp, are they something that I should be concerned about? or should they be included in a reef tank with fish?

Will having the live rock in the tank increase? or decrease the nitrates in the tank?

What about feeding the rock/life forms on it? What should I have on hand? how much? and how often?
 
I use club soda. When I squirt in the tank I use the coral feeder so I don't spray as much as I would with the turkey baster.

Precautions - don't put your hand near the mantis shrimp. They have the nickname thumbsplitter and remember they are quick. When we've had our pond tweezers in front of his hole he's snapped at them. It's best not to have another place they can hide nearby when they scoot out. That's why we squirt the rock in a separate tub.

Our tank had been running with a 65 gallon fuge with macro algae when we put the rock in. Our ammonia went up to .75 and then came back down to 0 not long after. We didn't find anything dead on the rock to remove before putting it in the tank.

Everything I've read about pistol shrimp is that they are fine in a reef tank as long as you don't mind the snapping sound. It drives some people nuts. We are leaving our 5 in the tank.

We followed Richard's directions from his website about feeding and lights. He says not to feed until your tank is cycled. He has a lot of good information on his site so make sure you read it all.

It's been a lot of fun finding all of the things that came with our rock. We are still finding new things every day.

We're getting our second batch of rock tonight. I'll let you know what we find in this batch.
 
Any new pictures yet? Sigh wish I wasn't going out of town I would have had my package by now. Stupid holiday. :)
 
We took loads of pictures but it took us until 2:30 AM to get everything in the tank. Nothing is really organized and those things that should be attached aren't. You won't believe the stuff Richard sent with this shipment. This definitely was Christmas all over again.
 
The really good news (we hope) is that we didn't find any mantis shrimp and we did dunk, swish and squirt before putting the rocks in the tank. We did remove a good many bad crabs. Found a lot of small pistol shrimp which we kept and a few other shrimp we aren't sure what they are but relatively few bad hitchhikers - or we were too tired to see them.

After I finish identifying things, I'll have to let you know about all the extras that Richard sent - including this gorgeous red clam.
 
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