Welcome to the HCA, nice to meet you!!! Aw, you crabs are precious!!
Very alert and healthy looking too!
I don't mean to pry, but you you mind if I give some advice? If you do, then feel free to not read the rest of this post, haha!
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Here is a basic care sheet, which I would definitely check out! Other care sheets (food, humidity, etc) are all over the site, but you seem good in the food regard! Anyway.
http://www.hermitcrabassociation.com/ph ... 51&t=92457
I would definitely recommend more substrate, traditionally an absolute minimum of 6 inches! I know it seems excessive, but it will keel your crabbies alive, with safe molts! You have EcoEarth, right? I can't quite tell, but if so, then big thumbs up. Great tank size too! To increase your substrate easily, I'd buy a bag of washed, undyed play sand (Home Depot). You can get a 50 lbs bag for pretty cheap! Sand mixed with EE allows firmness of the sub for tunneling (sand) while maintaining humidity (EE).
That being said, you might notice a drop in humidity if you do that. You might already know, but daily (or more, depending on your region) is necessary for your crabs well being, as they breathe through modified gills. Sorry if you already know, just in case! Once you have more substrate, I would place your thermometer/ hydrometer close to the substrate for an accurate reading!
For some reference: humidity should never dip below 70% for extended periods of time, and temp. should remain above 75 degrees F, and below 85.
It seems that you are serving fresh, awesome food for the crabbies, and multiple sources of water, etc. kudos to you for that.
In fact, idk why I'm going on. You have a lovely crabitat, the only (visible) problem is the substrate, which is very, very important. Hopefully this helped, if not, sorry! Great job, and good luck crabbing!!
EDIT: In review of my post, idk if it was totally inappropriate of me to correct you in an irrelevant thread. Sorry if so.
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