re: my crabs are dying too

[rica5tully]

How long should I acclimate hermit crabs? I bought three yesterday and floated them for about 15 minutes and then slowly put tank water in the bag (over about 10 minutes) to change the water parameters to the tank.

Of the three, two are not moving (one is upside down).

1) Do they need a perfect 1.0025 specific gravity? What if it's a point or two lower than that?

2) Do I need to acclimate them a lot longer than that?


ALSO: are lawnmower blenny's hard to take care of? I read somewhere that it's hard to get them to eat prepared foods?

Thanks!

[Guy W]

generally you acclimate inverts longer than fish. I do mine over the course of an hour... Floating them for 30 min. then adding tank water to the bag 3 times over the course of the next 30 minutes (about a cup every 10 minutes)... I've heard of some people taking even longer but that has seemed to work fine for me.

Now I've also taken a coral from the bag put it straight in the tank and it did fine. For what thats worth.

What are your nitrate levels in the tank? That could kill 'em if it's high. Also if you've ever used copper medication and the tank still has traces.

Guy

[rica5tully]

My nitrates are between 0 and 5, so I doubt that's it. I've never used copper in that tank.

Maybe my acclimation wasn't long enough. Thanks for your advice.

Is there usually a certain die-off with hermit crabs? In other words, if you put ten in the tank and acclimate correctly should you still expect 1/3 of them to die in the process?

[Guy W]

I haven't kept many hermits over the 2 years my tank has been setup but on 3 occassions now I have put about 10 to 20 (each time) in my tank and I seem to see a 10% to 20% die off in the first week, and an almost total die off over the course of 6 months (I've had on going nitrate issues I attribute to that however). However I did just pull some kind of huge crab out of my tank and I am thinking he may have had something to do with that, possibly.

This guy was the size of a half dollar and I had only recently saw him a few months ago but could never catch it. Still don't know what it was but it's gone now (not going to say where it went).

Guy

[Joey D]

well, im not so sure about the crabs, but im having sorta the same problems, and i think ive got it down. Crabs are cleaners that eat the junk off the bottom of your tank, if you have plenty of them , they may need to be fed enough. Put a piece of shrimp in the tank and watch them haul *** over to it and crowd it, its quite amusing. I've seen them steel it right out of my anemones mouth before. Now, they supposedly eat algae, and they clean your tank of meaty foods, but i'm also thinking they need seaweed supplements. Maybe they are dying from lack of nutrients, but you should definately also have some larger spare shells in your tank that they can move to as they outgrow their old shells. Ive seen my crabs swap shells many times, until eventually they run out and, if they dont find a new shell soon, will die. I have never seen them actaully swapping shells, so i guess this occurs with the lights out. One other thing, when buying snails, make certain they are actually alive and moving when you buy them, not just up in thier shells, because that usually indicates that they are dead. I bought four of them once and 3 were dead when i bought them, i just thought they were hiding in there shells because i could see thier foot, but they never came out. Be careful when buying livestock, if it's not healthy looking, do not buy it!!!

[kreblak]

I acclimate my hermits and snails for 90 minutes. I do 45 minutes of float time, followed by a half cupful of tank water every 15 minutes after that. By the time they are acclimated, they are usually itching to get out. The last batch of blue legged hermits I put in was so rearing to go they began crawling out of the bag before I could empty the water out! I almost had one go down the drain! I hand placed him on my live rock, and he seemed quite happy after that.

If you are losing hermit crabs, you might want to check for a cause. You stated that your nitrates are between 0 and 5 ppm. Have you checked them on an electronic water tester, or even a different test? I was quite surprised to learn that my nitrates tested differently on different test kits. I now do tests on Salifert and Tetratest kits to make sure I'm getting correct results. High nitrates (classified as above 50 ppm) are one possible cause of hermit crab attrition. Another is that you might have something actively hunting them. Did you get a mantis shrimp in on your live rock? Are you losing snails as well? All of these are possibilities.

Another possibility is this: when you add top off water or do water changes, do you use warm water form the tap? If so, that could be the root of the problem. Some hot water heaters sold nowadays have a copper overflow container, or copper lining within the heater itself. You could be unwittingly adding copper to the tank, which is exceedingly deadly to inverts.

Oh for salinity, mine fluctuates between 1.023 and 1.024. I assume you meant 1.025 and not 1.0025, as the latter is barely saltwater.

Finally, for a lawnmower blennie, get one that is eating well at the LFS. So long as you see it eat, you shouldn't have many problems down the road.

[mogurnda]

In my experience, hermits have been extremely tough. I have had some live for at least 2 years in NO3-filled FO tanks. Your acclimation sounds a little too fast, though. I float for about 15 minutes, then do 3-4 additions of tank water every 15 minutes. Early die off sounds like a problem with shipping, starvation at the LFS or something of that sort. It could be that they are not moving because they are stressed from all the changes they have been through. Plus, hermits tend to be more active at night. I would keep an eye on them for a few days and see if they perk up.

Maybe a shorter way of saying it is I have no idea, but keep an eye on them.

[liquafaction]

I acclimated mine for an hour. All I did was float them in there bag for about 20 minutes for the water temp to equal out, Next I poked a small hole in the bag (with a tooth pick) and let it fill up with tank water slowly. This took about another 30-40 minutes.

I have read with some of these people that ship inverts, they put little water in the bags. Having this small amout of water causes the inverts to go into a (hybernation), and they produce a small film around their gills. Supposedly this film protects thier gills, and there is little acclimation to speek of. All you are supposed to do is acclimate the inverts to temp change, not salinity change. I do not know if this is true.

[BrianH]

Liquifaction,

While poking a small hole in the bag may work for acclimating the new addition, you are also exposing your tank to the LFS water in the bag. IMHO I would try to keep the LFS water separate from your tank water since you do not know what is in the LFS water(chemicals, ICH etc.)

Brian

[liquafaction]

never looked at it that way, I see your point though.