Wow! This is was an old post...I'd completely forgotten about this.
She loves it! It took her about a month to really settle in. Now she could care less when we're in the room. I find her out basking all the time. It's held up really well. I built the base portion of the pond with a friend in 95ish...just added a little depth and the land on this redo. As far as gallons go, I have no idea. It's a bit larger than a bath tub though.
Hope this helps. Best of luck with your build! I had a great time with this. If I can help, let me know. I might have a few links to other walkthroughs saved somewhere if your interested...