The natural creeks where I've found brimleyorum were no more than 1-3 inches deep with very fast-flowing water, perhaps 1-1.5 feet across, and a very sharp incline. Very small stuff. I think a Paramesotriton-like setup will be too a little too still for them. They'd need some really agitated water because they asphyxiate really easily. One or two of those big airstones work nice. The juveniles seem most aquatic, the adults seem to like the stream/bank interface zone though they'll still prowl the deeper water occasionally.
Good luck with them Ed, they're a really neat species.