Flowering under T5. Full spectrum or all 3000K?

[Sunshine Closet]

8 sq. ft. grow area (4' x 2')
40000 lumens of T5 above
20000 lumens of T5 on each side
Total of 10000 lumens per sq. ft.


The opinions seem mixed on this subject, but I'd like to get my own input from you guys. Given the above setup, would all 3000k bulbs during flower be best or would something like 75% 3000k and 25% 6500K be better?

 

[ArcadiaAbsent]

Its a great question, I'd guess there's a sweet spot in there, some optimal balance that delivers peak results. That said, I'm not sure what it would be. There is plenty of discussion on this subject, the plant absorption light curves, the rhetoric tossed around by bulb manufacturers, several lumen vs. spectrum threads. Personally, my flowering girls get a limited spectrum in favor of max power with HPS lights. I have often contemplated offering a more complete range of light, but have yet to do so. I'm certainly not advanced or experienced enough as a physics student nor grower to offer definitive advice on this subject, but I will pose this idea to you. Since most T5 setups come complete with bulbs, generally the 6500k veg variety, why not consider running one grow with a 50/50 split or so, and a subsequent one with full 3000k bulbs? I think delving into some of the LED grow light posts may yield some advice as well, since many of those units offer on the fly color/temp adjustments. I'll see what I can dig up via links...

 

[Sunshine Closet]

I know that to the eye, a 50/50 mix looks just like natural sunlight so logically it would seem that a 50/50 mix would be optimal. Then again, some indoor techniques such as 24/0 lighting don't completely mimic nature and promotes faster vegetative growth (although some might debate this topic). I guess what I'm trying to say is that just because an indoor technique mimics mother nature doesn't make it the best way to go about things.

 

[ArcadiaAbsent]

I agree with your conclusion that mimicking mother nature is not necessarily ideal. Plants have shown to desire higher C02 than that which is natural, grow in artificial mediums at an increased rate, and respond well to some very extreme nutrient schedules. I certainly would not propose a 50/50 mix of light as an ideal spectrum, merely as a starting point if you have the funds, patience, and desire to experiment for yourself with the ideal spectrum of light. I truly believe the LED guys are your best bet to ask. If I were to take a stab in the dark though, I'd guess that 75% 3000K is the best option for balanced light spectrum. I'm very curious though to hear other inputs, so I'll continue to check in...

 

[ow.douglas]

I run a 50/50 mix start to finish with good results. I have not experimented with other combinations so I can't speak to that. Keep us posted, I would like to know what you land on and how you do with it.

 

[Dwezelitsame]

Im not sur if this helps you not t5. I use a hps -eye hortilux and a cmh- philips, side by side then i throw in my uvb at flower. I love mix spectrum i had read a lot of shit that said mh better to veg and to reduce stretch. Hps is the best to give you hard buds. Finish stage is better under mh to get more from final fatten of buds. Instead i give my plants both lights allthe time by spining and rotating pot position.

Ihope it helps

by the how is penatration with the t5's

1Luv

 

[Illegal Smile]

I used to use t5s to flower and used all 3000k. I couldn't get away from stretched plants and small buds. The penetration sucks. I went to hps and did not have the heat problems I used to have. I'll still use t5 for veg.

 

[Dwezelitsame]

thats what i thought and are not cheap either

 

[Kerovan]

thats what i thought and are not cheap either

T5's are not cheap. hps is a lot cheaper than t5's per lumen..

 

[q3aserver]

I used 8x T8 HO and 4x T5 HO in a 4.5'x2'x3' space. I cooled it with 3 PC fans and got 48 grams from 1 plant that was 1 foot tall taking up 1.5'x1.5' of space.

I flowered at 10 inches and I think this really hurt my yield. The main thing about the plant was the strength of the stems. I used 6400k in the T5HO and 2800k in the T8HO.

At maximum female capacity I would have produced about 6.5oz from my 4x2 10 bulb fixture.


I want to mention i did not have reflectors behind my bulbs. The fixtures are finished in black. That was probably a HUGE loss.

 

[Ronjohn7779]

T5's are not cheap. hps is a lot cheaper than t5's per lumen..

Not when you take into consideration the cost of the bulb, hood, and ballasts, fans, and ductwork need to keep an HPS cool (especially if your using a 1000w ballast you'll want to air cool it for most applications). Running the fans to cool the hps drives up your variable costs i.e. electrical costs. The price of the bulbs $70-120, the hood $180-255, a good ballast $299, and a fan costs $100-250. In the end that adds to your sunk costs. I use HPS for fruiting, for vegging t-5s are the way to go (they run cooler and need less accessories to operate efficiently, have a pretty long life time before replacement and are easily found at hardware stores). I'd never fruit with them though. That seems like a waste of time and money since the rewards isn't that great in the end compared to the costs of running a HPS in fruiting.

 

[Kerovan]

Not when you take into consideration the cost of the bulb, hood, and ballasts, fans, and ductwork need to keep an HPS cool (especially if your using a 1000w ballast you'll want to air cool it for most applications). Running the fans to cool the hps drives up your variable costs i.e. electrical costs. The price of the bulbs $70-120, the hood $180-255, a good ballast $299, and a fan costs $100-250. In the end that adds to your sunk costs. I use HPS for fruiting, for vegging t-5s are the way to go (they run cooler and need less accessories to operate efficiently, have a pretty long life time before replacement and are easily found at hardware stores). I'd never fruit with them though. That seems like a waste of time and money since the rewards isn't that great in the end compared to the costs of running a HPS in fruiting.

sorry, but I disagree. 1000W of t5's is going to cost a hell of a lot more. Besides, nobody said you had to buy 1000W or the most expensive parts you can find. A good hood can be had for $100. A good 600W ballast for $150, bulbs for as little as $20, you don't have to buy the overpriced Eye Hortilux bulbs. And you don't have to have any more fan power than you do with flourescents since flourescents put out just as much heat as hid lighting on a watt for watt basis.

 

[Ronjohn7779]

sorry, but I disagree. 1000W of t5's is going to cost a hell of a lot more. Besides, nobody said you had to buy 1000W or the most expensive parts you can find. A good hood can be had for $100. A good 600W ballast for $150, bulbs for as little as $20, you don't have to buy the overpriced Eye Hortilux bulbs. And you don't have to have any more fan power than you do with flourescents since flourescents put out just as much heat as hid lighting on a watt for watt basis.

I still fail to see your logic. In any case even if you go cheap on a bulb, ballast, or hood you'd still be popping an extra 70 bucks every 6-8 months with an HPS. Even at other wattages a T-5 is still cheaper in terms of total sunk costs, accessories, and maintenance (I've crunched the numbers before). I was just using a 1000w setup as an example even most 600w setups will need air cooling. The only setup I think HPS are slightly better than T-5s is with 400w bulbs. Then costs are somewhat comparable (in terms sun costs). You'd spend a bit more on bulb replacements but you'd make it up in electrical usage/higher bud yields per wattage.

Like I said the only time for higher wattages that an HPS beats out a T5 is when you do cost-benefit analysis. Buying, running and maintaining 600-1000w setups is expensive when you add in the sunk cost for accessories, bulb replacements, and running fans. The total electrical usage will have a higher lumen per watt cost (when you take the fans into consideration since fans are running while your bulbs are generating light). Like I said though the benefits of having an HPS setup for fruiting out weight the costs.

 

[Kerovan]

I still fail to see your logic. In any case even if you go cheap on a bulb, ballast, or hood you'd still be popping an extra 70 bucks every 6-8 months with an HPS. Even at other wattages a T-5 is still cheaper in terms of total sunk costs, accessories, and maintenance (I've crunched the numbers before). I was just using a 1000w setup as an example even most 600w setups will need air cooling. The only setup I think HPS are slightly better than T-5s is with 400w bulbs. Then costs are somewhat comparable (in terms sun costs). You'd spend a bit more on bulb replacements but you'd make it up in electrical usage/higher bud yields per wattage.

I never said "cheap" hood or ballast. I said "good". A good hood is $100-$125. You can get a "very good" lumatek 600W ballast for $150-$175. Flourescent bulbs effective life is a lot shorter than even cheap hps bulbs. We are just going to have to disagree on this. I too have "crunched the numbers", and t5's come out last for cost effectiveness. They are the best flourescent for growing, I agree on that. But they are ridiculously priced.

 

[q3aserver]

I went with T5 because it allows me to build my grow operation on a super tight budget. I am going to use T5 and T8 for veg int he future. So why not flower with it to pay for my HPS? I allowed me to buy lights every couple weeks rather then all at once. I looked at all my options in my budget at it came in the order of structure, venting, then lighting. For me Tubes were the most cost effective way.

You guys should also know, the T5 tube is not really any better then the T8 tube. When a T8 tube is run at 54 watts it puts out very close to the same light. I was able to overdrive all my T8 tubes on a budget that would have gotten you a good hps bulb.

This thread was about all red light vs partial blue light. Blue light helps produce strong stems and strong stems come in handy with heavy buds.

 

[Sunshine Closet]

As far as the T5 vs. HPS for flowering, sometimes using an HPS just isn't possible due to heat, the ducting/fans required, and other factors. Given the amount of lumens and side lighting available in my T5 setup, I'm confidient that the results will be more than adequate. Lumens are lumens and if you can get them where they need to go, they'll do what they're supposed to do. I think the key in this situation is the 20000 lumens on each side. If someone had only a high lumen T5 fixture above, sure the results wouldn't be spectacular because the penetration just won't be there. But with plenty of good side lighting and a steady rotation of the plants so they are exposed to plenty of light don't see how you could go wrong.

I've seen plenty of pictures (granted they were only pictures), of plants flowered under only CFL's that were plentiful and placed close to the plants. Those plants look no different than plants flowered under HPS systems. It's because again, lumens are lumens. This is all just my opinion, but I think it's a logically sound opinion.

Peace.

 

[Kerovan]

you are correct in a way, lumens are lumens. The spectrum also matters, but you can get the correct spectrums with flourescents also. And you can grow decent plants with flourescents, but you need a lot more than you have currently. Also you get more lumens per watt with hid, and flourescents put out just as much heat as hid on a watt for watt basis. So temps are the same in the room with either one if you have the same amount of light. Flourescents don't "feel" as hot as hid lighting simply because the heat is spread out along a much larger surface area of the bulb compared to hid bulbs, but they are still pumping out the heat.

my opinion on tube flourescents is that t8's are a much better value on a cost basis than the newer expensive t5's are currently. If you don't have enough money to buy a bunch of t5's and don't want an hid go to the hardware store and buy several t8 shop lights.

just my 2¢

 

[faller200]

Right now I use T5's for veg. I have 3 4' 4 bulb fixtures for a total of 648 watts. The fixtures were about $200 each. Now when I have new bulbs in them all they work very good. The problem I see is the fact that t5 bulbs lose brightness quite quickly and should be changed at least as often as HID bulbs. Run some new bulbs for 90 days then take one of those bulbs out and replace it with a new one and you will see just what I'm talking about. The new bulb will be much brighter than the 90 day old ones. T5's are not cheap. If I repalce all 16 bulbs at once ( and they should all be changed at once) with good bulbs cost around $200. I could use a 600 watt MH to cover the same space. One fixture and hood, ballast (way cheaper than the 3 T5 fixtures) and only one bulb to replace. Or 2 300 watt Induction florescent fixtures and replace bulbs every 5 to 7 years. Still comes out cheaper than T5's

 

[PetFlora]

From a lot of experimentation, I have concluded that plants do better when a broader spectrum is used

Next time I grow under my Quantum BB 8 bulb I will veg using ZooMed Tropical Wave (~5000K) + Quantum Grow (6500)

During flower will add a 1-2 ZooMed Flora Suns + Quantum Flower (2900K)

I own all except the Tropical Waves. If I didn't, I would use TW for veg and mix in a few FloraSuns for flower

I was using a bunch of different bulbs up until a week ago. Pistils were not browning, buds were not fattening up and tric production was less than I expected

I replaced 4 bulbs with Quantum Flower (2900K) kept 3 ZooMed Flora Suns and one UVL Red Life/Sun on the outside.

Buds are liking this combination


Here's a couple pics taken Sunday morning. They are farther along this morning



This pic is the mother of the 2 smaller clones. The taller 2 clones from the bigger plant. BTW, both are same strain, but F1 phenos


Here are clones started under a 3000K + 5000K ufo 90 + one 3000k/5000k led tube (18/20w). The color equivalency is ~ 3500K