Fish for crab control

[TopClamSkoo]

Are there any fish that would be useful to control pests like rock crabs?

Only one I could think of are dottybacks.

 

[Rtaylor]

Yikes…..typically you might find a hitchhiker or two, but not enough to necessitate ongoing population control. Anything capable of that would also eat any cuc you had. Predator fish like large wrasses, puffers, triggers, etc. will go after crabs. I don’t think a dottyback would do the trick, they’re just not big enough to go after large crabs.

 

[mdb_talon]

Some of the larger coral safe wrasses(melenarus, red coris) can decimate crabs(and snails, etc). Have to have a larger tank for these guys though so thats a factor.

 

[TopClamSkoo]

Wow. I always thought dottybacks would go after any crustaceans. Big or small.
Good point about the cuc's being in danger.

 

[i cant think]

Your best bet is going to be wrasses. What size tank is it?
Anything less than 4’ then you won’t be able to have many of the pest eating wrasses for this specific job unfortunately.

 

[TopClamSkoo]

Unfortunately, it's a nano 10 gallon.
So even the 6 line wrasse may be no go.
Only gonna have one fish in the tank and mostly zoas.

 

[i cant think]

Unfortunately, it's a nano 10 gallon.
So even the 6 line wrasse may be no go.
Only gonna have one fish in the tank and mostly zoas.

Unfortunately you are correct. I don’t think any fish will fit in that size that’ll eat them.

 

[TopClamSkoo]

I guess a dottyback would be in trouble with a rock crab? I did find one in my tank 2 nights ago. 1/2 size of a penny. Lil guy.
I don't think it would be. I'm more worried about my future corals. I'm glad I decided to QT my rocks in my display for the next couple months before I threw anything in. Problem is the crab lives inside the largest rock and I would like to avoid pulling it out to squish or crush the crab.
Hopefully I can trap it because I do want to keep it in a separate tank.

 

[TopClamSkoo]

Was hoping there was a fish out there that would keep pest crabs at bay after I attempt to pull this crab out.

 

[Duncan62]

Are there any fish that would be useful to control pests like rock crabs?

Only one I could think of are dottybacks.

Triggers live anything with a shell. Fun to watch.

 

[Bucs20fan]

Triggers are great, just not so much in a nano LOL.

 

[Bucs20fan]

Thats whats nice about having a fowlr tank right next to your reef, Ive got 3 species of triggers to choose from when critters are not playing by the rules haha.

 

[TopClamSkoo]

I read somewhere on the forum that some people just live with the rock crabs in their tanks... Ive found them before in my tank in the distant past, and I used to just squish them with a chopstick from a Chinese take out night before lol!

However, the crab I found was hiding in a small rock... this crab I found in my newest tank is in a very large 7 pound rock that I carefully placed in my tank before I poured in the sand... again, I hate to pull that whole rock out to pull the crab out... I doubt i can even catch him... id have to poke it and kill it, which I don't want to do..

Hopefully it can cohabite with my future dottyback and corals... LOL! but long term.. it may cause problems for my corals unless my dottyback can get em when it molts.

 

[Tonycass12]

Just make a trap out of a bottle and toss some frozen fish food in it for a night im sure any of your crabs will seak it out if you have any more in the tank.

 

[SteveMM62Reef]

Take the Rocks out, dip them in RO/DI Water, the crabs will do a quick exit, from the rock. Set rock aside, if you can, use water saved from water changes, till you can dip all the rock. Don’t get into a panic, if some of your corals don’t open for a couple of days. My Green Star Polyps didn’t open for a week and a half. BTW, If you have Amphipods that may come out of the rock. Save them by dipping out with a Brine Shrimp Net, or cut a couple squares of Filter Floss. Put them one at a time in the bottom of the RO\DI Dip, move the filter floss to the Aquarium, minus the Crabs, to your Aquarium. I’d wear gloves if you have Bristle Worms.

 

[Duncan62]

Triggers are great, just not so much in a nano LOL.

Just read back on tank size. I saw a clown less than an inch long last week. I wanted it but to pricy for me. He'd be cool for a while and even at that size will dismember larger crabs. But he'd need a place to go. I love tiny triggers. Same attitude as a big one.

 

[TopClamSkoo]

Take the Rocks out, dip them in RO/DI Water, the crabs will do a quick exit, from the rock. Set rock aside, if you can, use water saved from water changes, till you can dip all the rock. Don’t get into a panic, if some of your corals don’t open for a couple of days. My Green Star Polyps didn’t open for a week and a half. BTW, If you have Amphipods that may come out of the rock. Save them by dipping out with a Brine Shrimp Net, or cut a couple squares of Filter Floss. Put them one at a time in the bottom of the RO\DI Dip, move the filter floss to the Aquarium, minus the Crabs, to your Aquarium. I’d wear gloves if you have Bristle Worms.

thanks steve great idea! esp saving the pods! never thought to filter them out like that... cuz that was what I was worried about most... losing my pods if i do some kind of dip with my rock lol!