Ask Milo – Black Tahiti Sand

Jan asks:

I have a 55 gallon aquarium that was used about 6 months ago for tropical fish. It has Black Tahiti sand and I am wondering if I can move my 3 hermits from their 20 gallon over to this type of sand? Has anyone else used this substrate for their Hermes? Is it safe or too coarse?

Hi Jan!
I’ve looked up this type of sand as I am not familiar with it. The version I saw was a fine grade. While aquarium sands are ‘safe’ they really aren’t an ideal substrate unless they meet the need of being able to pack and hold like a sand castle. Sand that is too fine will often clump and stick to your hermit crabs. This could be dangerous if it dries and hardens. Sand that is too coarse will not pack properly. The ideal substrate allows for successful molting. The best substrate is play sand mixed with a small amount of cocofiber. There are various suggestions as to ratio but you should have more sand than cocofiber. The cocofiber allows for moisture retention and some aeration. You can add additional items to the substrate too (things like orchid bark, oyster shells crushed, leaf litter). If you still want to use your black sand you might be able to put it to use in your water pools.

Your good friend in a pinch,
Milo