Nice tank, i have the same model as you. Love the look of what you've done with it and i'm sure your betta will love it too!
Only thing i've found with it is that getting replacement bulbs for the light is a nightmare
I was worried abut getting a replacement bulb aswell, the guy in the pets at home store said they have replacement bulbs so as long as that shop is still there I should be ok. I also ordered some blue led's from ebay which I hope will be bright enough for the tank. Do you use the standard filter that come with the tank? I think it might be a little strong for Betta's so I've put it a few cms under the surface and have it pointing at the back wall of the tank so the current spreads out a little. What do you think of the standard filter?