Shame on you CG......the trap was right there in front of you, you're on a roll, giving ALL the rigt advice and then, bloooey! Went right ahead and stepped in it.
I know, what am I talking about?
You stepped in a pile of "A puffer's a puffer" and got it all over your shoe!
Most of the marine puffers offered for sale need a tank a LOT bigger than 46 gallons, unless you know that you're going to kill it in 6 months (and if you already know that, why buy it?)because in 2-3 years you're going to have a fish that will be at least 6" long (a dollar bill is 6" long...hold it up to the glass. OK, now how many dolar bills that are as wide as they are high, can swim around in that tank?)
BUT....some puffers are small and stay small!!!
First, you have sharp-nosed puffers, then others like the brackish species that actually do BETTER in a marine tank...now we're talking 3"-4", and there IS room for one of those in your 29!
Of course, there's even a glitch in this reasoning, still making a larger tank a better idea though.
Many of the little tobies and sharp-noses are also among the most aggressive in the whole family.
A Toby may well do just fine in a 20 or 29 gal. tank BUT is there any room for whomever he gets mad at to get away from him?
Think about how small your whole house is when your spouse, room-mate or parent is mad at you, OK?
That's a 100 gal. tank.
Now think of being locked in a CLOSET with that same PO'd person.....that's a 10-20 gal. tank!
Mike