The Moringa O. can grow very quickly, usually thin and very tall, but it needs to be top off quite often, if not it will reach for the sky. I had one that produced pods in 14 months. I now have a PKM 1 variety that is in a 15 gal. container, it was planted from seeds on Feb.14, and it is full of Flowers now, and measuring feet tall.
If this tree was in a 25 gal container it would probably be 1/3rd bigger than it is right now.I think.