If they're 18 inches long already they can be eating larger mice. Fuzzies or Hoppers would be more appropriate. If you do offer the larger meal as I suggested it will make a more noticeable lump in the snakes belly. It should also poop a bit more solid, as I imagine if they're eating pinkies their poop may be quite runny. There's a lot of ways to offer a snake food as far as a feeding schedule. If they're just pets and you have no intention to, or are not in a hurry to breed them someday then a few small rodents once every 5 days or so should be fine. If the snakes last meal is still visible in its belly then you may want to wait a bit longer. Tom Stevens
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