Dwarf Hermit Crab

[Mustafa]

Thanks for the update! I have no idea how long your species lives...but it seems like they are long lived from the information on the net...some species live up to 30 years. I wouldn't buy another one...the conditions in these tanks just aren't perfect for them.

[Corucia]

It's been some time since I last posted on this thread (+two years) but I thought I'd share a quick update. Both of my dwarf hermit crabs are still going strong. Over six if not almost seven years and counting. The only change is that their shells have now taken on a nice green patina to match their surroundings. I generally feed them a small amount of crushed pellet each week which they scarf up long before the shrimp get to them. Will be interesting to see how much longer they live in this environment (they are in a 3 gallon set-up)

[Mustafa]

Thanks for the update! Keep us updated over time! I'm very curious about how long they will live in a tank like that. So what have they been eating? Are you still feeding one crushed pellet a week? Have they ever molted? Usually, hermit crabs need larger shells lying around so they can switch shells after several molts as they are growing. Maybe they have reached their maximum size though.

[Corucia]

Mustafa, I’m still feeding them one small crushed pellet per week, which they pick off pretty quickly. I’ve never had a problem either with it fouling the water nor have I had an issue with algae overgrowth from too much waste/nutrients and it’s a pretty small tank. Only ~3 gallons. It’s been a very stable set-up now for almost 7 years.

On molting, they were smaller when I first got them and changed shells every year or so as they got larger (I used to drop in large shells from time to time). However, they have been in the same shells now for at least two years and appear to have stopped growing (or have just acclimated to the shell size they have). Interestingly, they also killed off all but one of the snails that I had and periodically took over their shells thereafter (I had both your snails and a slightly larger variant). There is one snail left who just got big enough to presumably shelter in place from their advances. They now peacefully co-exists - -the snail was actually on the back of one of the crabs the other day cleaning it. Will keep you apprised on how they do going forward.

[Corucia]

Just a quick update for the forum. After over eight years, I still have one hermit crab left and going strong (his roommate passed away about 6 months ago). He’s still fun to watch and adds character to the tank.

[Mustafa]

That's actually pretty amazing that they lasted that long! Did they eradicate your snail population, though? They may not be able to if the snails reproduce quickly, but they will definitely make a dent since they seem love eating them.

[Corucia]

Mustafa, they did wipe out most of the snails but two of the larger ones survived and they coalesced together for years. Ultimately the two snails died but the last crab is still going strong.

Separately, about three weeks ago I introduced dwarf Zebra reef hermit crabs into two of my tanks (four in each). Despite them being raised / keep in salt water I drip acclimated them to brackish over the course of 6 hours and seven of the eight are doing well in their respective tanks (one died within 24 hours). They all seem to be healthy an several have already swapped out of their original shells.

Interestingly they haven’t make a noticiable sent in the snail population and they mostly appear to be grazing on the algae in the substrate, on the rocks, etc. I’ll post an update next month.

[Mustafa]

Yeah, hermits tend to be tolerant of salinity changes as most of them live close to the shore where they can be caught in tide pools or other temporary pools. After rains those pools can have very low salinity. I'm just surprised that they can live at those low salinities permanently, or at least for years.

As for the zebra hermits, they appear to be one of the less predatory species...at least when they are small, so they may leave the snails alone...at least for a while.