I don't know what the lumen output is. Find out the K and then Google that specific bulb. If there are four bulbs in the fixture, just multiply the lumen by 4. You can find the bulb type (be sure it is T5) and the K on the bulb itself. Just guessing though, that fixture with four T5 bulbs will put out a good deal of light and would be adequate for several orchids you have beneath it. Just be sure to position the fixture within a few inches of the top of your orchid(s). The T5H or sometimes labeled T5HO would produce almost twice the light as the regular T5 bulb.
