Can't judge on the age thing. Not familiar enough with rosies. Be careful feeding him live (if that was what you were doing). You always run the chance of him getting hurt. Prekilled or frozen thawed is the way to go.
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Travis Rose
Lazy S Snake Ranch
3.7 Kenyan sand boas (various morphs)
1.2 Indian sand boas
0.3 Dogs
0.1 Cat
X.X Fish
0.1 Very understanding wife
2.0 Future Snake Lovers