You need lots of small things the little dudes will be able to wrap their tails around...you will need brine shrimp nepulai to feed them...or something else which is really really small.
Get some brine shrimp/artemia cists...a 2 liter plastic soda bottle (rinsed really well), an are pump with stone...fill the bottle about 1/2 with saltwater, put the airstone in the bottom...put in some cists and wait between 24-36 hours.
Once they start hatching...you will need to quickly either change some water out, or start harvesting them...a brine shrimp net (extremely fine mesh) is a much needed tool. Once they start hatching the amonia level in the container will go off the charts, and they will die quickly without new water.
For the babies...one would recommend about 1/2 of your 12 full, a very small sponge type of filter no small air bubbles if possible.
To feed, you need to saturate the water with the nepulai...leave them in for about 20 minutes....take as many back out as possible, they die quickly.
Good luck.