Clam eaten by hermit crabs

madducks42 · Jun 5, 2018

We picked up a 3-4 inch Derasa clam over the weekend. Our tank is over a year old and the alkalinity and calcium have been stable for a while so we figured we were finally ready. Been wanting a clam for a super long time : )

The LFS had some on sale that looked really nice so we went with the Derasa because we figured it would be a good starter clam. It seemed to be settling into the tank nicely, wasn’t showing any signs of stress. It was on the sand bed. Took some nice pictures of it last night. Came down this morning to discover the hermit crabs had eaten just about all of it! So bummed out right now!

TheSchwenkster · Jun 5, 2018

Sorry for your loss

. Seems like a really quick demise. How long had the LFS had the clams?

madducks42 · Jun 5, 2018

TheSchwenkster said:
Sorry for your loss . Seems like a really quick demise. How long had the LFS had the clams?

A few weeks. It didn’t seem like anything was wrong with it but we’re far from experts. It was starting to open and display its mantle. It wasn’t opening and closing or trying to move around. Currently I suspect it was healthy and the hermit crabs viewed it as an easy meal. I was up until about 2am last night and it was fine and the crabs weren’t anywhere near it.

RamsReef · Jun 5, 2018

Your clam was probably already dead / dieing.

That being said, I don't like hermits in my reef tank because you can never tell 100%.

madducks42 · Jun 5, 2018

I’d feel slightly better if the clam was dying before the hermit crabs went to town on it. Still on the fence about getting another clam with the hermit crabs in the tank. I could banish them to my frag tank because they’ve never bothered any of the coral.

TheSchwenkster · Jun 5, 2018

madducks42 said:
I’d feel slightly better if the clam was dying before the hermit crabs went to town on it. Still on the fence about getting another clam with the hermit crabs in the tank. I could banish them to my frag tank because they’ve never bothered any of the coral.

Might be a good start so you don't have a large crab gang roaming the tank looking for trouble. They are always at the scene of the crime so hard to say if they initiated the murder or just assisted. I agree with Ramasule, likely already on the way out

madducks42 · Jun 5, 2018

Haha. They're always looking for trouble. I actually like having hermit crabs in the tank. I know they have a reputation for causing problems but I think they're really entertaining. I might just pull some of the bigger ones out and leave a few little ones in the tank.

What are the signs to look for regarding a clam that's on it's way out? And aside from providing a stable environment and protecting it from hordes of murdering crabs, is there anything that can be done to save a clam that's not doing so well?

tvu · Jun 5, 2018

I have hermits and 2 clams. Clams are untouched by hermits.

I suspect the clam was on the way out.

DSC reef · Jun 5, 2018

Did you notice any new white growth on the clams shell? A clam can "look" healthy due to mantle extension but it could've been starving for quite a while. I wouldn't suspect the hermits as the culprit.

madducks42 · Jun 5, 2018

DSC reef said:
Did you notice any new white growth on the clams shell? A clam can "look" healthy due to mantle extension but it could've been starving for quite a while. I wouldn't suspect the hermits as the culprit.

I'll have to take a look when I get home. That's good to know though. I didn't know that was another thing to look for in terms of a healthy clam. I feel like the LFS don't have clams in stock often and they have a somewhat limited selection when they do. Is it better to order aquacultured ones from LiveAquaria or are those ones just as likely to be starving when you get them?

TheSchwenkster · Jun 5, 2018

DSC reef said:
Did you notice any new white growth on the clams shell?

^ agreed

Larger clams, 3" or better, are your best bet for success. If local, highly reactive to light, new shell growth, and some history in the LFS before purchase would be helpful, i.e. not fresh out of the UPS box.

cwalton00 · Jun 5, 2018

I had the same issue with a liveaquaria Divers den clam not to long ago. Woke up one morning to it completely gone. Not the clean up crews fault was just a dying clam. That said I picked up two Maxima's locally a little while back and they both are doing great so far.

cwalton00 · Jun 5, 2018

cwalton00 said:
I had the same issue with a liveaquaria Divers den clam not to long ago. Woke up one morning to it completely gone. Not the clean up crews fault was just a dying clam. That said I picked up two Maxima's locally a little while back and they both are doing great so far.

Here's a picture of the pair

DSC reef · Jun 5, 2018

madducks42 said:
I'll have to take a look when I get home. That's good to know though. I didn't know that was another thing to look for in terms of a healthy clam. I feel like the LFS don't have clams in stock often and they have a somewhat limited selection when they do. Is it better to order aquacultured ones from LiveAquaria or are those ones just as likely to be starving when you get them?

There's some good sponsors on here that sell quality clams. That said, I always like to visually inspect a clam I'm going to purchase. Make sure it has a good reactive response to shadowing, inspecting the shell for pyramid snails, look for new growth on the shell,etc. I also like to know how long the store has had the clam and what conditions they keep them in including lighting there under. If you get time look up some articles by James Fatheree. He's got some great info on clams and what to look for when purchasing.

hotashes · Jun 5, 2018

Do t forget to check how to 'burp' a clam if ever taken out of water for whatever reason.

Pretty important IMO.

A.

Jeff_H · Jun 6, 2018

Just curious, what type of hermit crabs do you have?

I have a Maxima with several scarlet hermits. The crabs often pick algae off it's shell, but have not bothered it or anything else in the tank to date.

Good luck with your next one!

madducks42 · Jun 17, 2018

Well I was hoping this would be a good news post but not so much. A week ago we returned to the LFS where we had bought the first clam. We purchased a nano tank from them that we were picking up. We mentioned that the clam we got on our previous trip met a quick demise and they offered to replace it. They said they’d had the clams for two months and they’d all been doing fine in the store. We brought the new clam home and it seemed to be doing fine. Left Friday night for a camping trip and returned today to find this : (

TheSchwenkster · Jun 17, 2018

Hmm, must be something in common. Was the new one responsive at the store? It was there long enough that it should have shown new growth. Did that appear to be the case? How long did you have it in your tank? Hope long was acclimation? What are your parameters? Can you get the parameters from the LFS and compare? Something in your tank could have a thing for clam meat now that you severed up a second dinner but hard to say. Don't happen to have any snails that could be whelks?

madducks42 · Jun 17, 2018

TheSchwenkster said:
Hmm, must be something in common. Was the new one responsive at the store? It was there long enough that it should have shown new growth. Did that appear to be the case? How long did you have it in your tank? Hope long was acclimation? What are your parameters? Can you get the parameters from the LFS and compare? Something in your tank could have a thing for clam meat now that you severed up a second dinner but hard to say. Don't happen to have any snails that could be whelks?

The new one was responsive at the store and in our tank, I can't say for certain that it had a quicker reaction time than the first clam because I didn't know to look for that at the time. I could see a thin white line around the outside of the shell, not sure how thick that line is supposed to be to determine good growth. It was in our tank for exactly one week, we got it last Sunday. I used drip acclimation for about an hour before putting it in the tank. The salinity at the LFS was the same as ours, 1.024. I don't think any of our snails are whelks based on the pictures of whelks I've seen. Also the snails have never seemed to bother the clams, it's always been the hermit crabs that are the ones having dinner.

Our tank has been fallow for 3 months because of an ick outbreak so it's been on a pretty light feeding schedule. I'm wondering if maybe it's because the hermit crabs aren't getting enough to eat so they went after the clam even though it was healthy. At any rate I picked up the clam shell along with all the hermit crabs that were munching on it and banished them to my frag tank. There are still a few hermit crabs left in the tank that I'll likely pull out before adding another clam just to rule out the possibility that they're the ones solely at fault for demise of our clams.