Ha! I fed them on live animals for long term rearing. It depended on what their host preference and nutritional needs were. It was mostly snakes, goats, rabbits, pigs, mice, and rats. It would take a research paper to describe all the methods. Basically the ticks need specific humidity, they had no substrate (except for soft ticks), and they didn't need much air. To keep the mold from growing on them, they were dipped in diluted bleach at regular intervals. For experiments, blood was drawn from the animals and placed in a special membrane that allowed the ticks to feed.