It's your basic glass 1 gallon "fish bowl" with about two, two and a half inches of "mineralized top soil" (basically soil that you get wet so it biologically activates all the dormant green critters in it, then pasteurized by drying/heating) and capped by about an inch of plain old sand (screened "construction" quartz sand, not pool filter sand or that weird white playground sand). There's a few ramshorns in there and some pond snails, a bit of duckweed on the top, but the other plants I've put in there seem to just get covered in diatoms and melt (Java moss and other non-surface floating plants like bladderworts and etc).

As far as care goes, when I feed I just turkey baster out a few portions for my fish and squirt them through a net to feed, and then I replace the lost water every few days from a tank (aged water). I BARELY feed this colony, it appears that the biological action taking place underneath the substrate is creating a very rich diet for the Daphnia.

There is also NO aeration in this tank (unlike the two other vessels you see on either side). I've found that without aeration, my "bare bottom" colonies crash in days instead of weeks, but this colony does not have that problem.

Also after about a week of reproduction outside of this vessel, the Daphnia I collect from the "child colonies" become progressively less "red" and instead take on a relatively clear appearance, with a very obvious "waste vein" visible.

These non-mudpuddle Daphnia are fed primarily on activated bakers yeast, powdered spirulina, powdered chlorella, and paprika. I was paranoid that the tablet form spirulina I was using was introducing some kind of possibly dangerous clumping agent to the feed so I changed to a powdered form I buy from the bulk section of Fred Meyers or WinCo.

(From the Greater Portland Aquarium Club Facebook posting of December 2014)