Lighting Question

Generally speaking, how well do high output T5s stack up against CFLs?

My reason for asking is that I have a 4 bulb, 2 foot T5 thing overhead, and just got two additional clip-on CFL lamps (each with a 23w bulb) to supplement for flowering. In looking up stuff about the CFLs, I found that approximately 100w (actual, not equivalent) per plant is recommended at minimum. Well, my T5 tubes are each 24w.

So I'm wondering whether one 24w T5 high output tube is basically the same as one 23w CFL (but for the one watt, of course), or if there is any appreciable difference between the T5 high output and the CFL. Any thoughts?

By the way, my grow area is about 2 foot wide X 1 foot deep X 2.5 feet tall, and the lights are all a couple inches from the plants.

I would really consider the lumens any bulb or light source you use is enough . First lumens , then spectrum . I use cfl's for beginning veg and use enough for 5k lumens per sq ft . From your area if you use 8 , 23 w cfl's you should have enough .

Personally I feel T5HO are more effecient than cfl's tho it wouldn't hurt to have cfl side lighting, btw each 2ft T5 6500K bulbs I believe puts out 2000 lumens, therefor you have 8000 lumens total, I could be wrong.

T5's are the best hands down.

They keep things short and chunky before flower like they should be indoor.

Thanks all. After some more research about lumens, I've learned that there is no solid answer. Some people say T5s are simply fluorescent lights, so in the 60-70 lumens per watt range (so for 24 watts, we're talking 1500-1700); some people say that HO T5s are in the 3000-5000 lumens per tube range; and some people take issue with the use of lumens generally, as it's based on perception (how bright something appears to the human eye).

So my question has evolved: is there any better way to determine light usage based on a solid, physical method, unrelated to human perception? Anyone with suggestions?

(By the way, at this point, this is more just for the fun of discussing science!)

When using cfls or t5s just put as many as u can fit in ur set up...I don't even count watts I just try to fit as many lights as possible in my space....that's how u make cfls workView attachment 2566717View attachment 2566718

RollUpMikey said:

T5's are the best hands down.

They keep things short and chunky before flower like they should be indoor.

Click to expand...

+rep - very nice looking plants.