Hi Lee and welcome to the forum!

It looks nice! What kind of frog(s) are you planning to put in it?

If you haven't already, you might want to check out this thread http://www.frogforum.net/vivarium-te...ng-im-new.html which contains some great info about cement backgrounds (provided by SludgeMunkey). A concern is letting the cement cure sufficiently to prevent it from messing up the pH, mixing cement + straight acrylic fortifier seems to fix this issue. If you went with cement + water, you may need a fair bit of curing time.