Natural sunlight?

[Don E]

Hi all-

I was just browsing Rcipema's (sp?) pics and he had a shot of his tank in morning sunlight. That's the first time I've seen anybody use sunlight on their tank. It got me thinking-

Is there any reason why you can't use natural light on your tank? If you can raise orchids and other high-light tropical plants on your windowsill in Calgary, why can't you do the same with corals?

It seems to me the biggest challenge would be heat control, but that should be manageable with air circulation (fans). You'd have to augment during the winter months to get your 12 hours of light, but what else is stopping reefers from saving huge bucks on lighting by using the Sun?

What do you think?

Don