Hermit crabs molting/dying?

[CindyK]

Hello,

I openly admit that I overstocked with hermits...I put 10 in my 75 gal. I don't have any algae yet, so I didn't want anything too reliant on algae for food that would starve, so I bought 3 red legged, 3 blue legged, and 4 scarlet hermits . Also 2 peppermint shrimp (for some aptasia).

5 days after adding them all I came home from work to find 2 of the hermits, a red leg and blue leg, out of their shells but (I'm fairly certain) alive. I ran out and bought spare shells of a few different shapes and sizes, threw them all in. The next morning the red leg was confirmed dead, what I thought was the blue leg was gone. Now I think I may have been looking at it's molt but I'm not sure, it seemed to be moving.

Today I found another, this one a scarlet, dead out of its shell. This time there are plenty of spares around.

Everything else is fine, water params have been stable with 0 ammonia/nitrites, nitrate varying 0-5, and alk around 8.1. Temp 78. The only other inhabitants are 2 Onyx clowns. I did a water change yesterday.

I feel like there is plenty of food. I feed frozen every other day and make sure to give a little extra for the inverts (probably way too much, part of the reason I have them). As I was typing this I watched a peppermint shrimp come out and snatch a leftover piece of something off the sand. None of the hermits or shrimp have even touched the dead crab, I'd get him out if I could reach him.

Whats the deal?

Cindy

[AboutAcans]

What chemicals are you using? What are you feeding? And what is in the tank?

[CindyK]

What chemicals are you using? What are you feeding? And what is in the tank?

No chemicals. Feeding Limpits Reef Buffet, just a general frozen reef food (IDK if it is available nationally)every other night, with pellets otherwise. Inhabitants are all listed in the OP but are 2 onyx clowns, 7 (now, I think) hermits, and 2 peppermint shrimp.

The tank is only a few weeks old but was thoroughly cycled and has had 0 ammonia consistently since inhabitants were added. Skimmer, lights, etc are all running fine. I have the beginnings of algae but not significant. I had an unexplained slight drop in alk but that was when I first set up, resolved before I added the inverts.

[AboutAcans]

I have the beginnings of algae but not significant. I had an unexplained slight drop in alk but that was when I first set up, resolved before I added the inverts.

Just answered your own question. I'd keep an eye on heat and test for nitrate, nitrite and phos. But the fact you even know you are showing the signs of the beginning of an algae bloom, means there's something out of wack and it's likely affecting the crabs too.

[CindyK]

I always thought a certain amount of algae was expected in a new tank? As I said in the op, temp is stable at 78, nitrite 0, nitrate 0-5. Phos test is on its way in the mail so I guess that could be something. I'm not sure how this shows anything out of the ordinary, can you explain?

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[CindyK]

Just answered your own question. I'd keep an eye on heat and test for nitrate, nitrite and phos. But the fact you even know you are showing the signs of the beginning of an algae bloom, means there's something out of wack and it's likely affecting the crabs too.
I always thought a certain amount of algae was expected in a new tank? As I said in the op, temp is stable at 78, nitrite 0, nitrate 0-5. Phos test is on its way in the mail so I guess that could be something. I'm not sure how this shows anything out of the ordinary, can you explain?


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[AboutAcans]

I always thought a certain amount of algae was expected in a new tank? As I said in the op, temp is stable at 78, nitrite 0, nitrate 0-5. Phos test is on its way in the mail so I guess that could be something. I'm not sure how this shows anything out of the ordinary, can you explain?


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Slight blooms. I have so many tanks I lost track. You're talking usually a minimum dusting of diatoms. Looks like someone sprinkled brown baby powder on the substrate. Anything outside of that and something is out of wack. Even then, the diatoms are still a sign that the tank just wasn't ready for crustaceans .

[gone fishin]

I would not be surprised if you got some algae in a new tank. Your hermits are scavengers so they will grab whatever food they can find. Once they left their shell they became pretty vulnerable.

[CindyK]

I would not be surprised if you got some algae in a new tank. Your hermits are scavengers so they will grab whatever food they can find. Once they left their shell they became pretty vulnerable.

Hi there....I thought of that too, after I wrote. But vulnerable to what? Idt the clowns would mess with them....but the other hermits and the peppermint shrimp seem like they might. But wouldn't they eat them right away then?

checked my params again tonight...no ammonia or nitrite, nitrates at 5ppm. dKH 8.624, but I did a water change yesterday so I'm not surprised. pH 8.0 Nothing is really changing except the alk meanders a bit. The algae looks like the pictures of most other new tanks I've seen honestly - it's just a tinge of green on the dry rocks (the ones I bought live are mostly coralline).

Cindy

[AboutAcans]

nitrates at 5ppm. dKH 8.624, it's just a tinge of green on the dry rocks (the ones I bought live are mostly coralline).

Cindy

Out of wack. Tank isn't ready for crustaceans. The only reason one would leave it's shell is to change into a new shell (well that or die). Your pH is WAY high. And coupled with even trace amounts of nitrates, it's going to cause undo stress to everything in the tank. It's not just one thing. It's several things going on that are stressing the members of your tank.

[gone fishin]

Hi there....I thought of that too, after I wrote. But vulnerable to what? Idt the clowns would mess with them....but the other hermits and the peppermint shrimp seem like they might. But wouldn't they eat them right away then?

checked my params again tonight...no ammonia or nitrite, nitrates at 5ppm. dKH 8.624, but I did a water change yesterday so I'm not surprised. pH 8.0 Nothing is really changing except the alk meanders a bit. The algae looks like the pictures of most other new tanks I've seen honestly - it's just a tinge of green on the dry rocks (the ones I bought live are mostly coralline).

Cindy

It is hard to say what went after the hermit. I would speculate it was another hermit. The clowns could have cruised by for a nip. It is hard to say why the hermit left the shell, maybe looking for a larger one or got pulled out.

5ppm nitrates is nothing to really sweat. I am not surprised at the alk wandering around a bit. I don't recall if your dosing anything for it, but at this point I really don't see the need for it. Your tank is still young and maturing.

In all honesty I would not worry to much about what happened.

[CindyK]

It is hard to say what went after the hermit. I would speculate it was another hermit. The clowns could have cruised by for a nip. It is hard to say why the hermit left the shell, maybe looking for a larger one or got pulled out.

5ppm nitrates is nothing to really sweat. I am not surprised at the alk wandering around a bit. I don't recall if your dosing anything for it, but at this point I really don't see the need for it. Your tank is still young and maturing.

In all honesty I would not worry to much about what happened.

Not dosing on a regular basis for the alk, I don't have any corals so I don't see a need. I did try baking soda once very early on...another thread, prior to all of this, and probably unnecessary.

Thanks for calming my jitters...I will keep calm :)

[gone fishin]

I would consider where you want to go with your CUC. I mostly use snails right now with a few stray leftover hermits. My reasoning is I got tired of paying for a mixed CUC only to have the snails get shell jacked. It seems even when the hermits had empty shells to choose from they always like the snail shell better.

I know quite a few folks that just use either one or the other.

[CindyK]

I would consider where you want to go with your CUC. I mostly use snails right now with a few stray leftover hermits. My reasoning is I got tired of paying for a mixed CUC only to have the snails get shell jacked. It seems even when the hermits had empty shells to choose from they always like the snail shell better.

I know quite a few folks that just use either one or the other.

I've actually been thinking about this too..I don't think I made a great choice but I'm not sure how to fix it.

My plan had been to add some snails when I had more algae...then when I overbought the crabs I thought, well, I'll just stick with the crabs for a while.

My concerns are that 1) they don't seem to be doing a great job. The carcass from the dead guy is still there, nobody is "cleaning it up". They aren't earning their keep. 2) The scarlet crabs are larger than I realized. I have a molly miller blenny in QT now, are they a threat to that fish (who hangs out on the rocks all the time)? I'm wondering if the larger crabs should be moved to the sump when he moves to the DT.

Your input is appreciated!

[gone fishin]

I don't think the hermits would pose a threat to the blenny. A healthy fish should be able to get away. I will say that I when I started I foolishly got a sally lightfoot crab, he became known as the spawn of satan. I believe the sally took some fish.

When I decided to shift over to all snails I just went the attrition route. I stopped getting hermits and slowly they have died off naturally. I like to get some dwarf cerith snails for the rock work. Those little guys get into the nooks and crannies.

FWIW I order from reefcleaners.

[CindyK]

I don't think the hermits would pose a threat to the blenny. A healthy fish should be able to get away. I will say that I when I started I foolishly got a sally lightfoot crab, he became known as the spawn of satan. I believe the sally took some fish.

When I decided to shift over to all snails I just went the attrition route. I stopped getting hermits and slowly they have died off naturally. I like to get some dwarf cerith snails for the rock work. Those little guys get into the nooks and crannies.

FWIW I order from reefcleaners.

Thanks! I will keep all in mind. I ordered some of my dry rock from Reefcleaners, was very impressed. I appreciate all of your support :)