Is a 400w MH really better than a 4-8 T5-HO bulbs for veg?
- Thread starter doniboy
- Start date
since1991
Well-Known Member
Old.post but its pretty obvious what the differences are. T5 6 or 8 bulbers with 6500k blue bulbs are great for getting small rooted clones off to a healthy start. As is a 400 watt halide. And despite what you may think...they both put out about 400 watts of "heat". Its just that t5's spread the light (and heat) out over a linear fashion whereas a halide..its more of a concentrated point source of light and heat. With smaller plants you will get a more flat top even plane of plants as opposed to a halide where you might get the canopy in the middle right under the light getting a little taller b3acause of this. With halides..think a concave bowl or stadium with the taller ones on the rim of the area to combat this. You will have move em around every few days or so. But they both work for the application and what we are trying to achieve. Where halides blow past t5's in veg is if you grow nice 18 to 24 " bushs before putting in the flower room. t5's...because of the linear light spread amd the nature of the bulb...just doesnt have the focused point source penetration to get down in there for a nice 2 foot bush. They both have pros and cons. If you have the veg space....use both for the intended application. Use t5's for smaller rooting and after root strike to establish a root ball and get em nice a even flatopped. What I like to call "prevegging". Then once they are 8 to 12 inches tall and healthy with mulitple even tops (4 to 6 inch square plastic nursery pots)...transplant up to a one to 3 gallon grow bag. Slap them under a nice blue 400 or 600 watt halide with a new 6500k or 7200k fixture. This is what I call the preflower stage. Your trying to build the framework foundation (potetntial branchy bud node sites) for what comes later. Let the little bush grow into the halides sunlike light spread into an 18 to 24 inch compact dark green healthy tight node bush. Then when the flower room(s) have an empty clean spot..throw em into 12- 12 flower. You should have a healthy established root system where the plant is on point...healthy and needing a drink every morning when the 18- 6 photoperiod kicks on. Thats when you know they are ready to flip into the bud stage. At least...this is how I do it. Sort of a two stage veg room. I also blast co2 gas in my veg room. The super healthy lush green thick compact plants just love this setup. Translates to maximum bud production in the flowering rooms. Depends on strain and grower/equipment/setup though. But I say..they both "shine" for what they obviously are and intended application and if you use them right.
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chemphlegm
Well-Known Member
depends on what expectations are. dollar for dollar, I believe in my quantum 485 watt t5 fixture.I havent changed bulbs since new.....2008!!. I used 400 watt mh for two years then went back to my beloved t5's for the win. winning on heat, winning on ballast life, winning on bulb degradation.
I admit while under my mh I experienced some accelerated growth, but that didnt matter to me, I'm in no hurry these days.
I admit while under my mh I experienced some accelerated growth, but that didnt matter to me, I'm in no hurry these days.
SoOLED
Well-Known Member
how much coverage do you need? an 8 tube 4'' T5 is about 379 watts. big and heavy. they both put out a lot of heat, maybe the T5 has more even coverage. that's what we used to use, was two big 8 tube T5 panels. hated changing the tubes on those things.
I think you could find a cheap led or cob solution. I think some one here made a 8 blub "brightstick" fixture from home depot for cheap, and all he did was cut the diffusers off so the LEDs where open.
I think you could find a cheap led or cob solution. I think some one here made a 8 blub "brightstick" fixture from home depot for cheap, and all he did was cut the diffusers off so the LEDs where open.
ilovetoskiatalta
Well-Known Member
In my grows the 315 cmh with a 4000k bulb in veg gave me the nicest growth in my many years of doing this.
I have used 400mh in veg as well as t5. My best plants with tight growth and lowest amount of heat for the smaller spaces has been the 315cmh. It is just another alternative. Operational cost is low and heat is lower than my 2'x2' 8 bulb t5, which i use for my clones. https://www.rollitup.org/t/club-315w-lec.904624/page-130#post-13669580
I have used 400mh in veg as well as t5. My best plants with tight growth and lowest amount of heat for the smaller spaces has been the 315cmh. It is just another alternative. Operational cost is low and heat is lower than my 2'x2' 8 bulb t5, which i use for my clones. https://www.rollitup.org/t/club-315w-lec.904624/page-130#post-13669580
whitebb2727
Well-Known Member
No it won't. Its 10 bucks or less for a t5 ballast. There will be 2 in a 8 bulb unit.
MichiganMedGrower
Well-Known Member
Since 2008?
I see slower growth and other problems caused by light degradation by 18 months on fluorescent tubes.
Can't get results I expect with old veg bulbs. I have tried. Strong fast veg leads to better flowers.
I am switching to a 315 cmh from my t-5's. Honestly my 400 blue mh did a better faster job than my t-5's.
I like them but plants can grow faster and stronger with hid.
MichiganMedGrower
Well-Known Member
Did you happen to compare the 4K with 3k for veg? I only have a 3100k Phillips bulb I am starting with.
chemphlegm
Well-Known Member
agreed they grow faster and stronger with hid.
yup, 2008 I use a meter full time and see some degradation, but in another room I use a 400 watt mh, its also years old with degradation of course and still rocks it, so..... my ushios dont degrade ever .....so far in flower.....maybe 2 years daily 12/12
I have a pack of bulbs waiting for my pseudo remodel soon I know I'll break bulbs moving lights/changing them....
MichiganMedGrower
Well-Known Member
Please post when you see any improvement. Old bulbs do not have the proper spectrum for max growth.
And all has burning bulbs degrade. Sharply. Even my cheap 3 in one garden meters crappy light sensor shows steady lumen degradation on all of my bulbs.
When it's showing low to me the plants always reflect that with their health and growth.
I go 9-10 months on Hortilux hps bulbs. 18 on stock t-5 6500's
And I went 9 with my first metal halide in 18/6 and it started to show its weakness. In 12/12 it couldn't do the job like a newer bulb at all.
whitebb2727
Well-Known Member
That's the thing with t5 bulbs. They only degrade so much and that's it. Hid bulbs continue to degrade.
MichiganMedGrower
Well-Known Member
In my research and experience this is not true. The coating degrades and the gasses degrade. Both things cause spectrum loss.
They are also the only bulbs I buy with questionable quality out of the box. No matter what brand I try some of the bulbs are bad or go bad quickly.
I feel like I have to monitor the tubes daily and always buy twice what I need. And seem to use them.
What brands are you having good quality with?
whitebb2727
Well-Known Member
Been having good luck with Agromax bulbs. On about 18 months on the set I have.
I'm sure ill need to replace them at some point. Can't remember where I got the info from.
I don't have a meter to check though. Going by eye.
MichiganMedGrower
Well-Known Member
Pretty sure Agromax is HTG supply. So likely Chinese made.
I have been using sunlight supply stock replacement ones and even the color of the end caps keep changing.
Maybe HTG has better quality control in place?they are self branded.
whitebb2727
Well-Known Member
They seem to bee good quality. Chinese doesn't always mean cheap inferior products.
MichiganMedGrower
Well-Known Member
I agree. My Chinese Squire Strat guitar plays very well and has held up for years. Made of real solid alder even and overseen by Fender for production.
All kinds of contracts are made with these huge Chinese factories.
whitebb2727
Well-Known Member
I had one bad bulb out of the bunch when I ordered and they sent a free replacement.
MichiganMedGrower
Well-Known Member
Out of how many may I ask?
ilovetoskiatalta
Well-Known Member
Yes first round I used the 3100k start to finish. Growth was good. This round I used the 4000k in veg and switched to 3100k in flower. The nodes on my afgooey are super tight. The Cali-0 kept a bit shorter.
Mind you my grows are small. But I was using 1000hps in flower and 400mh in veg for years and I thought they were the best. These 315 cmh do well for me, cost of use seems lower due to less heat(for my modest set up). If I ever do go back up to a larger grow I would use the 315cmh 4100k in veg exclusively. I would probably mix the de gavita and 315cmh 3100k in flower. Although @DemonTrich seems to have his flower room dialed in with all 315cmh with 3100k.