I guess I would be higher than the others, because of three issues:
Those puffers get quite large. I've seen one in a public aquarium that had to have been close to two feet.
Mixing full-size angels takes a lot of space. I would account for a couple hundred gallons for each.
Clown triggers are holy terrors.
For these reasons, I would look at something like a 12 x 4 ft. Around 800-900 gallons.