i have a new challenge that i need some help with and you guys always have good ideas. i have a birds nest acropora that has got crabs! at first i though they could just live together, but now i see damage to the coral and i've even seen them tearing little pieces of flesh off. i've tried to get them when they come out to feed on little bits of food i give them, but they are quick and hide way down deep in the base of the coral. i feel like i'm going to damage the coral to get them out, but eventually it will die from the crabs eating away at it....any ideas how to get these suckers out?????
how do i get rid of these crabs!!??
- Thread starter janet58
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roscoe
Well-known member
Tank the ccoral out and get the sucker. Better to have frags of it then a whole dead colony.
Herefishyfishy
Smart Bass
Strong tweezers or long noce pliers, turn them into fish food. Nothing lives forever...
nsamouroux
Well-known member
As a somewhat non-destructive way of catching them (won't damage your coral colonies, etc), take a soda bottle (20oz or 1 litre for an average size tank, 2 litre for a big setup) and clean it out VERY well. Cut the top portion off about 1" down from where the tapered section meets the cylindrical body of the bottle. Reverse the top section and put it inside the main section so the screw-top is inside the base. Drill a LOT of small holes in the body of the trap so water can flow through and not stagnate and bait the trap with a small piece of frozen shrimp or home made fish food. The circulation holes are important because if you don't allow the water to freely escape the trap will turn into an ammonia bomb overnight in your tank and could cause some major die-off.
The carnivorous pest crabs (and some critters that you might want to keep, like cleaner shrimp) will enter the trap through the lid and be stuck inside until you remove them. It might take a few tries, but you'll eventually catch the critters you want to remove. Just be sure to remove and replace the bait every day to prevent nitrate / ammonia in the tank from the decaying material.
The carnivorous pest crabs (and some critters that you might want to keep, like cleaner shrimp) will enter the trap through the lid and be stuck inside until you remove them. It might take a few tries, but you'll eventually catch the critters you want to remove. Just be sure to remove and replace the bait every day to prevent nitrate / ammonia in the tank from the decaying material.
ajnweb
Well-known member
I recently removed all of the emerald crabs out of my tank using am empty starbucks iced mocha bottle. The bottle is glass, has a tapered neck with an opening about 1.75" across, perfect for catching crabs. I filled a mesh media bag with some frozen fish food and placed it in the bottle, then placed the bottle in the tank slightly tilted up against some rocks. OVernight I had cought all the hermit crabs and emerald crabs, and started cathing them within about 30 minutes of placing the trap. The mocha bottle is small enought that it is easy to place just about anywhere in the tank. Good luck!
If you are worried about nitrate/ammonia spike just use the bottle for a few hours at a time. I don't think you need to use a large amount of food anyway.
If you are worried about nitrate/ammonia spike just use the bottle for a few hours at a time. I don't think you need to use a large amount of food anyway.
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nsamouroux
Well-known member
I've heard of using petroleum jelly in copious amounts for that type, and if that doesn't work there's always gasoline / matches or napalm :lol:
nsamouroux
Well-known member
A lot of crabs are more active nocturnally which is why I would leave the bottle in overnight. I am pretty sure there's a mantis shrimp SOMEWHERE in my tank that I have tried catching using the bottle trick, which is how I learned about the thing turning into an ammonia bomb. I didn't put any ventilation holes in the bottle trap, so the next afternoon when I got home from work (trap put in the tank the previous evening before sleepytime) I went to check on it and found three dead skunk cleaner shrimp, a dead fire shrimp, and a few dead / dying hermit crabs. The smell in that bottle was horrendous! Apparently the ammonia built up to the point where the critters that entered the trap died VERY quickly and compounded the effect. Since that little adventure I always ventilate the things as much as possible and haven't had any problems with the inmates dying 
Myteemouse
NOTHING
I just keep shaved down..
roscoe
Well-known member
I just keep shaved down..
You are f'ing sick!!!!! No one wants to know what you keep shaved down LMAO:lol::lol::lol::lol::lol:.
Myteemouse
NOTHING
I don't know what you speak of
I keep corals shaved down so they don't get crabs..
I have one emerald and he behaves very well with my short haired corals.
I keep corals shaved down so they don't get crabs..
I have one emerald and he behaves very well with my short haired corals.
