A 29 is TOO SMALL:
1.These guys 'poop like elephants'. I hate trying to vacuum a small tank - I always seem to be too low on water to finish. I have 2 6-inch ghosties in a 55 bare bottom tank now - looking for their new home - a 220 if I can find/afford it.
2. They like to 'scoot' around - usually nose down - and check out their options for lunch. This is just too small a footprint for them- especially if they are sharing it with other fish, plants, ornaments, etc.
3. They are sensitive fish - if the water parms get out of whack they will feel it. I prefer larger tanks - more forgiving and easier to keep within acceptable ranges.
A 29 is fine as QT tank... but then you need atleast a 72 for him.
Think of it like buying a 'great dane' and then wanting him to live in a medium sized dog house. You may be able to squeeze him in - but he certainly would not be very comfortable.