I thought crabs (and shrimps and suchlike) are really sensitive to osmotic
changes...

If loads of water has evaporated due to high heat thus raising the SG and
then you top up with fresh water in one go... thus lowering the SG the
crabs will really suffer..

Same as if you do a waterchange with a drastically different SG... you say
its only 1.021, what is it normally

Do you have an auto top up system?

Im pretty sure this is the case.. never happened to me but like i say im
sure ive read it somewhere, read loads though and can never remember it all

Could be a shell mind....

W


"Larry W" wrote in message
...
Two months ago I lost the air conditioned in the house for a week. The
tank
got way too hot and I lost a lot of stuff. I lost during the crash a
porcelain crab, decorator crab, anemone crab, 2 shrimp and 2 emerald
crabs.
I have since replaced 4 different kinds of hermits, 3 kinds of snails, 3
anemones, some fish, cucumber, nudabranch, horseshoe crab and 2 emerald
crabs. Yesterday I found one emerald crab sitting pretty as you please on
top of my mushroom leather, dead, today I found the other one sitting on
some rocks, dead. Everything else seems ok as does that water parameters.
The skimmer is working just fine. The salt is a little low at 1.021.
Any Ideas on what could have killed the emerald crabs. In the past I have
had little luck with them also.

Thanks