If they ingest abit of eco earth its not the end of the world, its made so fine so the animal can pass it easier. Not saying let him run free eating substrate because that would be a problem but a little bit shouldn't hurt him, that's why tong feeding is the best way to feed these guys if they are being fed in the enclosure. To answer the feeding question you could offer food every second night from the last time he ate, meaning if its feeding night and he doesn't happen to eat try again the next night. If he eats that night then skip the next day and feed again on second night.