DIY UVA/B
- Thread starter bk78
- Start date
Rocket Soul
Well-Known Member
Kingbrite or cutter. Or waiting for some blue Buddies from @Grow Lights Australia
Rocket Soul
Well-Known Member
Nice diode count/$$ do you have any idea of dimensions? Looking forward to see your uv results.
bk78
Well-Known Member
38 inches long by 2 inches wide.
Rocket Soul
Well-Known Member
Coverage isn't only dependant on wattage, spread/hanging height matters a lot as well.
The HLGs are made to hang high, about 24" or so on a 550-type setup. If you have bars pushed down low there's 2 issues:
Not enough spread. I don't know the exact ins and outs of your meijiu light but say you were able to spread your bars out freely and you put only 2 bars over a 4x4 and hang them and your typical hanging height. Is the coverage acceptably even? Probably not. so 2 uv strips are going to have more or less the same spread.
Second issue: with low hanging bars you might end up in a situation where you get uv burning due to the added light being too intense at low hanging height. Too intense uv will seriously hurt yield.
If you want 8x4 coverage with approx 12-16" hanging height: I suspect you'll need 5 bars in total with around 1.5 ft distance between them. There isn't anything that says you need to have even numbers per 4x4 if your in a bigger space.
On uv+660+730: if you already have some 660 I'd probably go for separate 730 and far red bars, both on their own dimmer. It's nice to have dial in control so you can have the far red compensating for the stretch inhibition of the uv. Also you would probably not be able to do end of day treatment with a far red + uv bar. I've seen your setup and I get the feeling that you're after a monster rolls royce kinda thing: don't cheap out on possible features, make sure you can at least try them out in order to maximize your space.
The HLGs are made to hang high, about 24" or so on a 550-type setup. If you have bars pushed down low there's 2 issues:
Not enough spread. I don't know the exact ins and outs of your meijiu light but say you were able to spread your bars out freely and you put only 2 bars over a 4x4 and hang them and your typical hanging height. Is the coverage acceptably even? Probably not. so 2 uv strips are going to have more or less the same spread.
Second issue: with low hanging bars you might end up in a situation where you get uv burning due to the added light being too intense at low hanging height. Too intense uv will seriously hurt yield.
If you want 8x4 coverage with approx 12-16" hanging height: I suspect you'll need 5 bars in total with around 1.5 ft distance between them. There isn't anything that says you need to have even numbers per 4x4 if your in a bigger space.
On uv+660+730: if you already have some 660 I'd probably go for separate 730 and far red bars, both on their own dimmer. It's nice to have dial in control so you can have the far red compensating for the stretch inhibition of the uv. Also you would probably not be able to do end of day treatment with a far red + uv bar. I've seen your setup and I get the feeling that you're after a monster rolls royce kinda thing: don't cheap out on possible features, make sure you can at least try them out in order to maximize your space.
bk78
Well-Known Member
I mean I did post in the proper section “LED” not sure why you are recommending me tubes?
bk78
Well-Known Member
You’re right. I’ll just wait on getting the 730 if that’s where I want to go in the future.
Once again I always appreciate your input rocket
Rocket Soul
Well-Known Member
The problem with the t5 uv is they don't play nice with other bar like fixtures:
The pure uv bulbs need loads of hanging height in order to not burn the shit out of the plants. This means you have to hang the whole light at +24" which makes a bar light kinda pointless.
The way around it is by doing bulbs with lower uv output. But then you end up having to run them during much more time; more energy consumption. Another issue with t5 pure uv is the "pulsing". Every time you fire up a bulb you lose a bit of bulb life, more so than keeping them on all the time. One of the uv strategies is to do pulses; 5mins per hour or so. With bulbs this means lowering life time considerably where as with leds you wouldn't have to worry about that.
I agree that t5s used to be the best solution a year or so ago. But with new bars style fixtures and the fact that covid have made all sorts of uv diodes more available and less pricey I'd say you're probably better of with leds today.
If you have the possibility to custom in series leds also give you very good options for customizing your uv spectrum, picking out how much of every nm.
Rocket Soul
Well-Known Member
If you have the $$ why not all in? These strips are going to cost a bit in shipping due to the size and this seems to be a really good deal for the price. I really think it's a good idea to add both at the same time as the 2 spectrums kinda works against each other, compensating.You’re right. I’ll just wait on getting the 730 if that’s where I want to go in the future.
Once again I always appreciate your input rocket
I'd be all over this if they just a little shorter, I need 90 cm to match them with fotops boards.
bk78
Well-Known Member
The 30w versions are 30” long