Culturing ultimately depends on the number of frogs you keep and the species. I keep (not including tadpoles) 13 individuals of different species so I make at least two new cultures a week to keep up. I also culture hydei and melsnogastor. Hydei for my large species and melanogastor for my small ones. Hydei tend to boom twice over four weeks and the melanogastor produce pretty consistently. If I am in a pinch and low on hydei I’ll feed the melanogastor as a backup. Joshs frogs sells starter kits and in my opinion their culture media is the best so they would be a good place to start stocking up. If you are starting with say two frogs you’ll want at least 3 cultures going at a time. One producing to feed off, one to seed new cultures and one as a backup.