While I'm throwing in things I've forgotten to say: there's no rush on removing small gorilla crabs, or, really, small mantises. They have to get big to cause any real problems.
Edit: or, ha! Bait!
Edit: or, ha! Bait!
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lol, if it was just the one mantis, I would give him a free ride. They max out at about 2” and on their own won’t do a lot of damage.
LOL, i just wanted to say that good or bad, that is quite impressive!
I've set up a bunch of tanks from large to small with TBS rock. Some rock that was fairly new/young and other rock that had been down there for many years. Small pieces to almost boulder sized. I've had a range of critters, the worst was a large stone crab. I've had my share of mantis, but even on the biggest tank with the oldest rock, i still only had 3. Never even knew there were octopus!
I'm sorry I can't answer your question since I've never been in this situation but wow. Super interesting. Hopefully you can at least knock down the mantis population with some suggestions here. Whelks you can pull out when you see them, same for gorillas, isopods will age out rather quickly. I have a mantis in my current tank, just the one as far as i've seen, and in the more than 1 year that I've had the tank running, this is the first time that a mantis hasn't come fully out looking for food, allowing me to grab him. That little sucker is just continuing to enjoy the free escargot!
I must be really slow.. LOL - I think I ended up catching 2 with tweezers. I used a tall glass leaned up on rock and put a silverside in the bottom. Cut a piece of eggcrate to fit tightly in the glass to hold the silverside in.Yup, caught one of them giving my stylophora tester a hair cut. Managed to take him out pretty easily. Have a pair of 22” tweezers I use for that job.
I’ve been told a customer in Nebraska had a clutch of 60 hatch in his tank.
LOL, i just wanted to say that good or bad, that is quite impressive!
I've set up a bunch of tanks from large to small with TBS rock. Some rock that was fairly new/young and other rock that had been down there for many years. Small pieces to almost boulder sized. I've had a range of critters, the worst was a large stone crab. I've had my share of mantis, but even on the biggest tank with the oldest rock, i still only had 3. Never even knew there were octopus!
I'm sorry I can't answer your question since I've never been in this situation but wow. Super interesting. Hopefully you can at least knock down the mantis population with some suggestions here. Whelks you can pull out when you see them, same for gorillas, isopods will age out rather quickly. I have a mantis in my current tank, just the one as far as i've seen, and in the more than 1 year that I've had the tank running, this is the first time that a mantis hasn't come fully out looking for food, allowing me to grab him. That little sucker is just continuing to enjoy the free escargot!
This is one of my most used reefing tools.I must be really slow.. LOL - I think I ended up catching 2 with tweezers. I used a tall glass leaned up on rock and put a silverside in the bottom. Cut a piece of eggcrate to fit tightly in the glass to hold the silverside in.
Here is a sugestion. Pull 1 rock and give it a dip. Use a white bucket or similar.I’m debating doing a hyper salinity dip this weekend but don’t want to shoot myself in the foot by removing both friend and foe from the rock.
I have so many good things on the rock that really come alive at night, it would be a real shame to loose all of that.
So still up in the air on what to do.
Get a six line wrasse to catch and eat the small ones or perhaps a copper band?
Else it may be bottle traps but you never gonna get them all.
Most nights after lights out, I spend about an hour with a red torch removing things - plenty of whelks, some Eunice worms, got a couple of crabs but even the really small ones hold on for dear life it’s nearly impossible to catch them.
As for the possible octopi running around.
You never gonna see any of them until they quite a lot bigger and can do some serious damage.
Thanks for the info.Here is a sugestion. Pull 1 rock and give it a dip. Use a white bucket or similar.
You can put the good stuff back and just remove what you dont want.
Sometimes I will suspend the rock in the bucket just below some tank water.
Many things will jump off the rock into the bucket.
About 10 min will do and it wont have much effect on the good life from my past experience.
Anyway start with one and evaluate.
I removed all rock in a established frag system sometime ago to remove bubble aglae.
I thought I had 3-4 emerald crabs.
Their were over 12 as I remember.
I just scooped them up and back they went. Their was several peppermint shirmp I had thought were dead along time ago.
Keep us posted.
This is a great idea! Thank you for sharing this,it will be helpful to many I’m sureHere is a sugestion. Pull 1 rock and give it a dip. Use a white bucket or similar.
You can put the good stuff back and just remove what you dont want.
Sometimes I will suspend the rock in the bucket just below some tank water.
Many things will jump off the rock into the bucket.
About 10 min will do and it wont have much effect on the good life from my past experience.
Anyway start with one and evaluate.
I removed all rock in a established frag system sometime ago to remove bubble aglae.
I thought I had 3-4 emerald crabs.
Their were over 12 as I remember.
I just scooped them up and back they went. Their was several peppermint shirmp I had thought were dead along time ago.
Keep us posted.
I’ve also read up on seltzer water.I still have a scattering of tunicates/sea squirts (same animal), feather worms, and bivalves on my rock after over a year. Decent feeding helps, and smaller ones have a better shot at staying fed. You might try taking the rock out of the water and sort of shaking/tapping it for a bit to scare everything that can close up into closing up, so that your tunicates and such will hopefully be less likely to take in over-salty water.
Or, honestly, I'd still go with traps, tongs, and time. A frag rack or two on the glass will let you safely add corals, since gorilla crabs can't climb clean glass.
I’ve also read up on seltzer water.I still have a scattering of tunicates/sea squirts (same animal), feather worms, and bivalves on my rock after over a year. Decent feeding helps, and smaller ones have a better shot at staying fed. You might try taking the rock out of the water and sort of shaking/tapping it for a bit to scare everything that can close up into closing up, so that your tunicates and such will hopefully be less likely to take in over-salty water.
Or, honestly, I'd still go with traps, tongs, and time. A frag rack or two on the glass will let you safely add corals, since gorilla crabs can't climb clean glass.
He's cute! He looks like Gonzo from the muppets.As promised here is a picture of one of the mantis’s in the tank. This guy has a bunker setup right in the front of the tank and green in colour, so fairly easy to see compared to the bigger ones hiding under the rocks in the back. Now that I know he’s there.
This one is probably about 3 to 4mm wide and guessing no more than 20mm long and very skittish.
Used the flipper magnifying glass to help take these pictures and still had to put the camera on 5x zoom.
Couldn’t photograph more than the eyes as it’s a quick little bugger.
This may seem a little extreme but it's effective...Fill a five gallon bucket with fresh water and drop the rocks in. it doesn't take but about 5 minutes and most of the nasties will bail out of rock..Then agitate the rock around around vigorously for a minute or 2 and the rest of the crabs should come out too..Hi guys.
Got some really great live rock from TBS full of life, sponges, micro brittle stars, ect.
But have a problem with a number of undesirables that also arrived on the rock.
Upon initial inspection I removed an octopus, 2 mantis shrimp, a couple of gorilla and decorator crabs…. And some whelks.
However, now that the rock is in the tank and cycling, I found a couple other things.
A clutch of octopus eggs- which can easily be removed.
But….
From what I can see it looks like 20+ mantis shrimps ranging in sizes from 0.5 inches to another big one at 2 inches. Also suspect some more nasty crabs as well as the initial cleanup grew is all but wiped out in less than 4 days.
Any suggestions on how to get these critters off the rock?
Obviously, I will take the rock out again and inspect by hand but don’t want to do anything as drastic as a fresh water dip as that is gonna kill a lot of beneficial flora and fauna as well.
Any suggestions and advice welcomed.
This is veryyy risky, but it will definitely work at getting every live aspect off of that rock.This may seem a little extreme but it's effective...Fill a five gallon bucket with fresh water and drop the rocks in. it doesn't take but about 5 minutes and most of the nasties will bail out of rock..Then agitate the rock around around vigorously for a minute or 2 and the rest of the crabs should come out too..
if any stars or good critters come off the rock try to moon recover them quickly and put them in a q tank
I'm FAR from an expert, but it seems to me that this would thrust many delicate organisms into immediate osmotic shock, and cause more die off than it would help. Are you specifically talking about aquacultured live rock from places like Tampa Bay Saltwater that comes teeming with life? Can you link to another post supporting this? I'm genuinely asking. Thank you for your help!This may seem a little extreme but it's effective...Fill a five gallon bucket with fresh water and drop the rocks in. it doesn't take but about 5 minutes and most of the nasties will bail out of rock..Then agitate the rock around around vigorously for a minute or 2 and the rest of the crabs should come out too..
if any stars or good critters come off the rock try to moon recover them quickly and put them in a q tank
That's going to kill a lot of things, yeah. It'll work out fine if you want the live rock exclusively for algae and bacteria (which are admittedly the most important parts), but if you like all the macroorganisms, you should probably not do that. Pretty sure TBS says somewhere on their site not to do it.I'm FAR from an expert, but it seems to me that this would thrust many delicate organisms into immediate osmotic shock, and cause more die off than it would help. Are you specifically talking about aquacultured live rock from places like Tampa Bay Saltwater that comes teeming with life? Can you link to another post supporting this? I'm genuinely asking. Thank you for your help!