Emerald Crabs and Stomatella Snails

[Argentum]

Hello everyone, I was wondering if anyone here has any any experience with emerald crabs interacting with stomatella snails?

I have a small population of stomatellas in my 20 gallon tank and was looking at adding an emerald crab to work on some newly arrived bubble algae that has started to get a foothold on a few pieces of my live rock. I have some patches of hair algae and quite a few stalks of palm calerpa that would likely keep the emerald fed as well, in addition to normal feeding in the tank. I know that most reports for emeralds state they are opportunistic, with the general caveat they tend to behave better when they're well fed, but I'm wondering if anyone has seen emeralds go after stomatellas actively or if they've experienced a crash in their stomatella population after an emerald crab introduction?

Right now, I'm erring on the side of introducing one with caution and a very close eye, ready to return him should he begin to go rogue, but any additional first-hand knowledge would be great! Thanks in advance.

 

[KrisReef]

My surviving Stomatellas I rarely see. I have had wrasse and other omnivores for a few years. They went into the wife’s fish tank and now I have a pair of Tomato clown and for awhile a Copperband who moved into the display sump because he’d eradicated the aiptasia there. The remaining stomstellas (sic) are all hiding underneath things and probably coming out for the night shift on the reef.

Add a crab and shift your population to the night shift or extirpate them with the opportunistic feeder since crabs also work graveyard? If you try it let us know what happened, I’m thinking a small tank will not provide enough cover and space to allow for coexistence of crab and snail.

 

[Argentum]

Thanks for the info Kris. Yeah, I'm still on the fence about it, but I do have a lot of very small crevasses and tight rock work that even an emerald crab would likely have trouble reaching into that a stomatella could hide in. I do love having stomatellas though, so I'm gonna watch the crab like a hawk and if he even hints at any predatory behavior, he's gonna be outta there.

Anyone else have any first hand experience with emerald crabs and stomatellas?

 

[damsels are not mean]

Sounds like you just don't want a crab. Why can't you just remove the bubble algae yourself? You're a lot faster and more targeted than a crab can ever be.

 

[Argentum]

Lol, I re-read my posts and I can see how it might seem like I don't want an emerald crab, but I do, I just am worried about the stomatellas. Having the emerald to work on the bubble algae would be perfect, but I also like seeing an active little green crab grazing in the tank. That's one of my favorite aspects of my saltwater tanks over the years, having so much diversity in one tank compared to freshwater, and crabs are a key part of that, as long as they behave (which so many do not). I just don't want that addition to come at the expense of the stomatellas, which are my favorite snails.

 

[damsels are not mean]

Lol, I re-read my posts and I can see how it might seem like I don't want an emerald crab, but I do, I just am worried about the stomatellas. Having the emerald to work on the bubble algae would be perfect, but I also like seeing an active little green crab grazing in the tank. That's one of my favorite aspects of my saltwater tanks over the years, having so much diversity in one tank compared to freshwater, and crabs are a key part of that, as long as they behave (which so many do not). I just don't want that addition to come at the expense of the stomatellas, which are my favorite snails.

I always advocate manual removal when possible, but I understand the desire for an emerald crab as a user of this resource (bubble algae) you have been blessed with (lol). If you like the crab, get the crab! Get a female if you have the option to pick. They have smaller claws and supposedly are better behaved (dubious claim, imo, but the small claws make it a bit credible)

If you just want an excuse to get a crab, why not a more benign one like a porcelain? They couldn't harm a fly and are very fun to watch once they get comfortable. They are technically not true crabs, but they look and act the part without any of the bad.