Hello OldSparky,
Welcome to the boards and I'm flattered by you're asking for my input.

I have built two different hybred lights, one I have used for 3 years or so now and the other was just a few months then gave it up and I have to admit it was a failure.
First the failure; it consisted of 2- TI problooms mounted in a frame with 4- 4' T5s 3000k driven to VHO levels (85w/bulb), 2 bulbs to each side of the TIs. It just did not achieve good light mix, but did square off the lights footprint to cover a 4'x4' area. Problem was the center was recieving just LED light, a few rows on either side got a mix and the outer rows only got T5 light. It still beat a 1k HPS but was using 1000w total and I found I could get the same results the the 2- TIs (660w total) and a light rail.

My other hybred did not start out to be one. It was going to be red and white LEDs but I got burned by a chinese mfg of the whites and had to shit can them. I used T5s instead (full spectrums then now 2700k) because I had so much invested and the design was physically good.

This light is in my personal grow, where I use a GI Grow rotating garden (144 plants) that's been heavily modified. At the center is a 6"dia boroscilicate glass tube that needs to produce light in a 360 degree pattern. I used a 24" piece of architechural aluminum in a octogonal shape, mounted inside the glass tube. Each side has 1- 2' T5 2700k driven to VHO levels (40w/ea) and a row of 30- red 635nm Crees that are 2w nominal tho I drive them at 650ma and they produce abt 1.75w each. So there is 320w of T5 and 420w 635 red for a total light of 740 watt. It outperforms the 1K HPS it replaced.

At the time I built it the best red LEDs seemed to be the Cree's. I only wish some good 660nm LEDs were available at that time, I think it would work even better. BTW I like those PPL lights, looked at some 105w PPLs awhile ago but when I went to buy a fixture they had discontiuned it. You are absolutely correct about the amount of blue in a flouro, even a 2700k. I originally used 2' T5s that were "full spectrum" cause I was gun shy from my white diode experience but when it came time to change bulbs I figured out what you have, there is a large blue bulge in the SPD of all fluros.

IMHO if you could combine one or two 55wPPLs with a row of those Osram 660nm LEDs in the same fixture you would achieve a better blending of light wavelenghts. I think that if they are in seperate fixtures you may find what I did with the 4' hybred light, uneven blending. It is my belief that the octogon hybred works so much better because of the closeness of the LEDs and T5s. It is possible that the fact the plants are moving also helps the plants to see all the light better (kinda like a light rail).

Thanks again for asking for my input and I'm more then willing to kick ideas around with you. I should note that I also use some other supplemental lights with this. Good luck and good designing and growing to ya. :thumbsup:
oldmac Reviewed by oldmac on . Questions for Oldmac - Hi Oldmac ā?? Iā??ve been lurking around here for a while, and decided I needed to join up and see if I can tap into some of your experience. Iā??ve seen that you use a hybrid fluorescent/led fixture and was wondering if there were any pitfalls that you would pass along so that I can jump over them! I have been using a homemade fixture that utilizes (6) 55 watt PL-L lamps, changing out the lamp spectrum based on the plant maturity. The fixture uses reflectors that are 4ā? x 22ā?, and what I Rating: 5