When the snake is full grown. The divider is only $20 plus a little shipping! Its worth every penny especially bc you can use the rhp!
I will say that my super pastel is 600ish grams and 3ft long and is in a v400 which is about the same size of a T8. He wouldn't eat consistently so I put him in there and it worked, last 10 feedings successful. Also a 1072g Ivory has been in a 48" cage so I'm buying him off a friend and putting in a T10. These are not typical cases of bps, they usually need small spaces.
What will probably end up happening is the snake will outgrow the 10g but won't be big enough for the full T8 yet so you will either have to buy a size in between or a divider so I say get the divider now and put snake in half of T8 and move divider as its grows to big for half. It will be less hassle in the long run and the T8 won't be sitting around forever, it will be in good use.
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