I bought the wrong Grow/Bloom hanging lamp for my mini cattaleya.

[starryfield]

I bought a Sunleaves Pioneer IV from Rogue Hydroponics. Claims to give out 20,000 lumens. Can't get it up past 10,000 which is too low for minicatts. Tell me what to buy and I will do it. Kathleen

[raybark]

I think you are improperly assessing lighting in general.

Let me share a couple of comments. A 4 x 4' T5 fixture should be good for about 90 lumens per watt x 54W x 4 = 19400, so is probably rated correctly, but please consider that the rating is the initial output, that is, the sum of the radiated light right at the entire surface of the bulbs. There are any number of reasons that the measured output might be lower:

• Not all of the light is directed or reflected out of the fixture to the plants, due to the presence of the bulbs themselves, blocking some of the light, the quality of the reflector, and the nature of light emission - light emitted from the parts of the bulbs facing each other will never reach your plants.
• Light falls off as the inverse square of the distance. The intensity measured two feet from the fixture will be one-fourth of the intensity as it would be meaured at one foot distance. The moment you move away from the bulbs, the intensity is lower.

I would also comment that "10,000 lumens" is PLENTY of light - even for vandas - but the lights have to be close enough to the plants that the foot-candles (lumens per square foot) are sufficient. Put your catts 3" from that fixture and you'd likely burn them.