No shielding from sunlight. I am breeding for an orange tilapia. So I WANT the sunlight on them.

Not sure why, but UV light seems to make them more orange. Like I said, may not be the light...maybe just cause they are outside, who knows. But outside is better. Light is better...and the lilly pads don't bloom without good light. Worst thing that happens is a little green water, and who cares? The tilapia have gill scrubbers and this just adds to their food.