i have a 29g high. would it work to drop the water in it to have a half water half not tank. with angels and a few other fish then a island for the newts?
Not a chance, for a couple of reasons.
One is that the angels wont have enough space, and the other is that the angels are very inquisitive, and may well bite the newts just to see what they are.
Another reason is that newts really require cooler water, even if the tank was big enough to accommodate for both species you would have to subject one species to unnatural temperatures, which commonly causes health problems.