Folks, if you've recently upgraded or renewed your annual club membership but it's still not active, please reach out to the BOD or a moderator. The PayPal system has a slight bug which it doesn't allow it to activate the account on it's own.
Would it be ideal, of course not. But with that said, I had a very small hippo and a kole in my old 44 pentagon which was very similar measurements to your tank. They were just fine. I knew they had to be upgraded and I eventually did.