There is much to be said on this topic. Basically the color of the light is an important factor. In a simplified view light can be said to have a certain color...and as the color temperature increases it appears whiter to the human eye. All of the cheaper lights are designed with the human eye in mind...and not fish.
The color is rated in degrees Kelvin(K). As an example the light color ... at the equator ...at noon is about 6500K. You would be looking for bulbs in this temperature range (and up ...to say 20K by some accounts). The cheapo lights are usually below 4000K.
It is an important thing to learn...fish are not cheap dates.
