Limpets????

[medusamedusa]

Was looking at my tank this evening and noticed a part of the rock was moving ,on closer inspection realized it was some kind of snail did some research on the web and found out its called a limpet,,,,the only thing i couldnt find was information about what it actually does,,,is it a good guy or bad???? any info greatly appreciated thanks in advance

[ATJ]

Limpets are generally herbivores (eat algae) and so they are good to have in the tank.

[kmk2307]

Hi medusamedusa,
I agree with ATJ that limpets are mostly beneficial algae eaters. Sometimes they will find a soft coral they like to eat. Mine have been model citizens in my reef with the exception of liking to graze on a Cladiella coral. I have numerous corals including other types of Cladiella and theres only one they bother. If you keep corals just keep an eye on them. I have heard they also eat soft encrusting sponges which tend to grow here and there on live rock.

HTH,
Kevin

[wishmaster]

Here is some general info on them
http://www.odc.ucla.edu/html/body_limpets.html

[medusamedusa]

Thanks u guys,,,,,ill keep a close eye on this guy,,,i do have corals and i wouldnt want him eating any of them ,,,i did notice that a sponge that was growing on a rock dissappeared ,,,,i bet the little bugger ate it!

[hubris007]

I've never had any noticible probs with limpets. My tank is overrun with them, but i think my blue legs just eat them when they want a snack.

[mogurnda]

I have watched them eat sponges, massive stonies and soft corals. My siderastrea always looked awful after they passed over, but has managed to recover.
As you can see from the other responses, I think my experience is in the minority.

[mogurnda]

and another thing...

from the limpet link
"They eat algae, colonial tunicates and sponges by scraping rocks with their radula. Entirely herbivorous."
I guess sponges and tunicates have packed up and switched kingdoms.

[hubris007]

perhaps if you took a little better care of your sponges and tunicates and didn't let algae grow on them, the limpets wouldn't feel the need to clean them for you. Poor little limpets, always getting blamed for things that are out of their control...hehe

[kmk2307]

LOL - Hubris... Don't blame the limpets, blame society!

I can't say if mine are eating sponge or not. I haven't noticed any sort of change in the population of sponge in my tank andI've never seen them grazing on sponge but I hear they do like to eat some kinds.

Kevin

[mogurnda]

Guess I'm not very good at nurturing. It's pretty obvious when they're eating sponges, their little heads are buried in the sponge, and a little divot is left when they're done. It's actually not that bad, unless the sponge is small and you have too many limpets. What got them evicted was their gnawing on the toadstool.

[musicsmaker]

I just removed a keyhole limpet from my tank because he was bulldozing things over. Other than that, no real problems. He did a good job of keeping the glass clean. People who frequent my house have referred to him as the "Chinese hat thing". He is in a tub with some cured live rock for now.

[hubris007]

is it really obvious they are eating the sponge or is it possible they are eating whatever is on the sponge and end up taking the sponge with it. Isn't that esentially what happens when pencil urchins decimate the coraline on live rock? They just mow it all down to get to what they want...

[kmk2307]

Hey hubris, I thought you were totally joking. Nope, I think that limpets just eat organisms other than algae. In my case the only thing i've seen them eat that wasn't algae was a soft coral but it didn't have algae growing on it. Lots of molluscs are carnivores and omnivores so it wouldn't suprize me that these guys eat things other than algae. I think pencil urchins will eat some soft corals and the like as well.

Kevin

[mogurnda]

Hubris, I thought you were joking, too. If one does a little research, it is clear that keyholes are known to eat things other than algae. My other snails never do more than a polite pass over the sponges and corals, never burying their heads in the sponges and going "yumm yumm..." Regardless of whether the sponges and corals are intended victims, I don't really like having them chewed on, and the limpets will stay in the fuge.
Once again, if anyone wants some slightly used limpets, I will be happy to bag them and ship them. Hubris?:D

[musicsmaker]

While we are talking about these things, does anyone know how they reproduce? I keep finding babies.

[mogurnda]

I believe they have direct development, and are hermaphroditic like most gastropods. If no one else can give a better answer, I'll look it up tonight. I can imagine never getting anything done if I brought my invert zoo texts to work.

[mogurnda]

Musicsmaker,
After a little research (emphasis on little) it looks like the guys external fertilization, releasing eggs and sperm into the water. They (at least Diodora) have a non-feeding planktonic veliger stage before settling as little limpets. So I was wrong about direct development. It seems unlikely that the gametes and veligers could escape your skimmer, pumps and inhabitants, so maybe they just came in as very small hitchhikers.

[musicsmaker]

Originally posted by mogurnda
it looks like the guys external fertilization, releasing eggs and sperm into the water. So it takes two to tango in this situation?

[mogurnda]

I think so. Many gastropods with internal fertilization have both parts, but can't fertilize themselves. It's possible that limpets could fertilize their own eggs in the water column, but I can find nothing specific about how mating actually happens. Sounds like a good one for Dr Ron.

[DgenR8]

I have a bunch of keyhole limpets in my tank. I've been plucking them and putting them in my 'fuge lately, as at least one of them has taken a liking to my Xenia. I couldn't understand why I didn't have any Xenia to frag in a while, and on a stakeout, I found a keyhole eating it.
I have seen them spawn as well, releasing sperm/eggs/both?? into the water from the hole in the top of their shell.

[musicsmaker]

I have seen them spawn as well, releasing sperm/eggs/both?? into the water from the hole in the top of their shell. I want to think that it is both, but as mogurnda has said "Sounds like a good one for Dr Ron." I know some things can pop up for months after starting a tank, but it has been a lot of months. The one I saw recently was almost too small to see. It has been my experiance that these things grow pretty fast.

[aquaman67]

I had some limpets hitchhike on my live rock. I had no idea what they were. After doing some reading, the only bad thing I remember was that their scraping ability is so strong that they have been known to scratch acrylic tanks. So if you have an acrylic tank, be careful and keep an eye on them!