Micro worms - Moisten oat meal and sprinkle yeast over top. Add the culture and let it sit in a sealed container with air holes. Replace every 1 - 2 weeks, when it starts to turn black it needs to be replaced.
Vinegar eels - Half an apple in a 50/50 mix of apple cider vinegar / water. Add the culture in a sealed vented container (I stuff filter floss in the vent holes) These cultures will be good for approx 6 months or so.