Tub Size

My ball python (Sobek) is roughly 29" or so in a 15qt. tub. My question is, is it time to get him a bigger tub or let him get a little bigger. thx for the reply and sorry if it's a stupid question.

I think a general guideline is: length of tub plus the width of the tub equals the length of snake. If the snake is longer than the added measurements, get bigger tub.
Not stupid question and I hope its not a stupid answer.

I say once they are a year old you can move them to a 32qt tub or when they are around 500 grams.