Well, I have a pair of 7 month old peruvians, and the breeder made a point...about a dozen times...of not overfeeding, and instructed me to offer a decent sized meal (enough that it makes a lump in them for a 1-3 days)every 3 weeks. They said really though, just keep an eye on the animal. After it deficates, give it a couple days to see whats going on and if nothing more comes out, give it some food. I've tried to stick to the 3 week thing though. There's really no way to rush these animals to breeding size...almost every breeder will tell you a young overweight snake will just throw mostly slugs. So do the 14-21 days thing, keep the animal healthy, and be patient 
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Cycling: Trio Black Rat Snakes
Together: Poss Het Axanthic male Ball x Normal-no mating witnessed yet.
Chris LaViola
CMLReptiles
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CMLReptiles@aol.com