Up and down and up and down

ok, So this morning they were all down, and now 3 are up! Kiri is by far my most active crab in the tank. Then Walter and Rascal... :) Rascal has been hanging out in the gravel.. he dug a little pit.. I wonder why when there so much EE/Sand to dig in? oh well. The tank is starting to smell... well.. like dirt.. which i think is the smell before mold, so Im thinking of changing it when I get paid :) now just have to decide on a color!maybe, Glow-In-The-Dark?