Substrate care and changing landscape

[Swimkim]

Hello,
A couple of general questions about the substrate. I have the play sand and eco earth mixture. My humidity has been between 76-80% about 3-4inches deep. Is there ever a need to moisten the substrate? Also, when is a good time to change up the landscape? For example I want to add in a small pool with a bubbler and exercise wheel? I have 2 crabs. Not sure if I am seeing the same crab over and over or if they rotate with hiding.

[curlysister]

If your substrate dries out, you will need to moisten it. How fast it dries out will depend on a few factors, like how much ventilation/ air flow there is, whether your heat pads go below the level of your substrate, etc. I goog test is to poke soething like a chop stick down along the glass to the bottom - you should be able to tell if the substrate holds it's shape or collapses in, and then you aren't risking poking down onto a crab who is underground.