The correct lighting in an aquarium is very important; it should help the fish to look their best, allow plants to grow, and above all be safe - we all know care must be taken when using electricity near water!
Safety first
This has to be the key concern
Good lights for the fish
Good lights for plants
The biggest killer of tropical fish is overfeeding. Uneaten food decays and pollutes the water, even with adequate filtration. Adult fish should remain unfed one day each week, and almost all commonly available species will be completely fine if unfed during a two week vacation