To Cheri and Ginger & Lee -
Thank you so much for your advice. I realize you're not supposed to handle the frogs too much [and I thoroughly wash my hands before I do] but when I do hold him, he comes alive and turns bright green. Once back in the tank, he turns dark brown and tries to get out. Given what you said, I suppose the little guy is freezing to death. But it is winter, and I simply wasn't sure it, by wanting to keep him warm, I wasn't imposing a very human perspective on one of nature's creatures who may live by very different rules.
I am out the door for a larger tank and plants and goodies right after I do a little bit of reading about what plants to buy. My whole front yard is tropical - so this guy definitely found the right person to landscape his tank!
Talk to you all again soon -
b