Tropical Fish Enthusiast
Those plastic cubes look like attractive mini-terraria. Ultimately, they are impractical for little things like AIR CIRCULATION, but they are good for temporarily shocked plants and seed germination.
You will find that people vary somewhat in their media mix. Mr. D'Amato isn't the end all, but he is certainly excellent for those who new and intermediate hobbyists, who need SOME direction. Personally, I like to mix sand & peat and then topdress with LFS (long fiber sphagnum). Ya can't go TOO wrong with that. Just make sure you wash and rinse all media.
Jimscott, I agree that D'Amato isn't the end all for info but it is always a good starting point and reference. But from my internet searches about Mexipings, most say that they like a more airy and looser soil. And yes, I always wash all cp planting ingredients well before using. I then save all the leftover water (distilled$ or rain) and give it to the ferns, gardenias, and other acid loving plants.