Hi there:

Sure, a 35-40 gallon is nice for a specimen that size, but most average about eight inches or so in length. They are also usually curled away in hides, so a single specimen or pair could be mantained in that sized tank. I have only seen caecilians as large as yours in zoos. That's wonderful that yours is that large. You must be taking excellent care of it. I would love to see some pictures. While most people don't, I see every Typhlonectes as having its own form or facial expression.

DAVE