What they do? Provide light, I'd guess. What are these "bulbs"? Are they actually tinted green and orange? Are they actually PC flourescent tubes? Do they have any identifying markings or labels on them? Can you provide any kind of info whatsoever to give us even a tiny, little chance of giving a useful response?
You only need "special" lights for f/w trops if you want to grow plants or want to bring out your fishes colours.