If plants only lived in the shade, there wouldn't be so much sunshine in the world and there's nothing that needs more sunshine than a cactus. Whatever lights you eventually choose, make sure they're full spectrum (no funny colors - the plants will sort it out) and rated to 6000k to 6500k or 2000 lumens per square foot or .... Brighter the better. After you choose, buy twice as many lights as you think you need.
Only the plants directly below the lights will get the full benefit of all those Lumens and Kelvins. The plants on the edges of the light are in the shade. So if you have a spotlight, you may have enough sun for one plant. If you have a 4 ft tube light, you have enough sun for a 4 ft long, single wide row of plants. You can use that to your advantage if you are growing plants with different light needs: full sun plants directly under the lights and succulents or other lower light plants on the edges. You will have to raise or lower the lights (or plants) to get the most benefit. You can judge the effectiveness of your lights by holding your hand under the lights. Watch how sharp a shadow your hand casts as you move it closer to and farther from the lights. Full sun casts a sharp shadow.
So about those funny colors.... If plants only needed red and blue, the sun would be purple. The sun is white, its shining in all the colors of the specturm. Earth plants have evolved under our Sun - they use ALL the colors of the spectrum.
Sunlight is just another needed nutrient, like nitrogen, phosphorus and potassium. But instead of minerals, these nutrients are colors. Plants do use more red and blue than other colors just as they use more N, K and P than other minerals. But that doesn't mean plants can live without the other colors anymore than they can live without calcium or magnesium or iron. Plants even use some green, although we have all heard forever about plants reflecting green so don't use any.
Cactus need an amazing amount of light to be happy, succulents are easier under lights. But with enough lights you can grow anything.
