Has anyone tried using these lights? Does anyone have an opinion on how good or bad these may be?
I havent seen them, but I do know that t5’s can grow some amazing buds. It looks like those are to compliment their main Veg bulb. The spectrum in those look good enough, but I personally havent tried do grow using t5’s
A guy in the lab has them. They seem awfully expensive for what you get. If you’re limited to growing with t5’s I would maybe grab like two of the 660’s to add to 6 standard bulbs for flowering. Otherwise I think you’d be spending way more money than necessary.
I noticed that even the 660’s don’t have much for far red (720-740), which I am starting to find out, is important for bloom.
Far Red (730nm is best) is used to switch the Phytochrome far red to Phytochrome red and make the plants switch to night time mode faster. While not needed, it definitely helps, because without it. The plants can take up to 2 hours to switch to their night cycle. With the Far Red you can effectively do this in about 15 minutes.
Some benefits of this include a longer lights on schedule. Some people like to use 13.5 hours on and 10.5 hours off for a few weeks then switch back to 12/12. Or if you were to leave it on 12/12 it could speed up your flowering times by about a week.
An easy way to add far red is buying RapidLEDs flower initiator puck, or you can purchase some cree xp-e gar red diodes and make one yourself, which is what I essentially did. I didnt use Cree but the principle is the same.
660’s don’t have any. When you find them they’re usually like 650nm-660nm, and that’s all of the light they emit. So if you’re looking for far reds they’re not in 660nm diodes.
I am in line with @Aolelon, although I’m not exactly sure what the advantages of 730nm over something like 720nm would be? I know at 720nm we’re still at about 25% rqe, and should be plenty to good hold the end of far red production.
I used 6500k bulbs in veg and used the eye hortilux flower bulb combo for flower which actually worked really well my northern lights and my agent orange and my purple haze finished under them and turned out great the purple haze was a bit whispy but the other 3 were nice and dense
My other 4 plants finished under my cob fixture and the yield and bud structure was way better but the bulb combination on the t5s worked very well
Tbh I’m not sure if there is a huge difference between 730nm and 720nm. I’ve just read that 730nm is the best at switching the phfr to phr and to get there most diodes use 720-740nm. But I might be understanding it a bit wrong