waterdog,
Mantis are EASY to take care of. I had mine in a 5g Eclipse Hex 5. He hate everything from crayfish to shrimp. He didn't need live food, though it was fun to see him "hunt" when he had the opportunity.
He was unable to damage the acrylic. Maybe had he been in glass, but I doubt I would have had a problem with glass, either.
For water changes, I made sure never to put my hand in the tank....
They are super cool and very active--and not too expensive. I'd recommend them to anyone who has a taste for the "odd" SW pet.
The greener you get them, the longer they'll live (they say about 5 years). Mine was brown, meaning he was close to his last molt.
I work on WIBA. Usually conservative, on occasions socially liberal.