Half Coconut shells in the tank?
You've all seen the cleaned but slightly hairy half coconuts they sell as terrarium and crab housing but can they be submerged and survive? Do they mold or leak tannin? Any experiences with coconut shells? I had hopes of covering one with substrate so only the half hole showed like a little cave with a trail of white sand and rive rocks as front door steps but maybe I should try something else?