[baddagger]

Hello, right now i have my flower room setup with 9 gavita 6/750 running at 825 boost mode. the room is 12 feet deep by 14 feet wide. I have my gavitas set up in 3 rows of 3.

I want to add in mh to balance the spectrum to get better yield, my last round i ran one 1000 mh in 1 row and that plant colas where double the size then my the round im running now on the same plant with out mh in the mix.

So wanted to ask some input on what would be the best to mix in. I was thinking of putting in two 600 watt mh in between each row so it would be hps,mh,hps,mh,hps. Would that be a good mix ? would 600 watts be to much or should i go two just 400 watts mh instead?

also im trying to figure out what would be the better mh spectrum to mix in as well, i know the 10k is suppose to be a finisher but would going with that with the gavits give better light balance? I know its recommend to use 4k because its suppose to be more balanced , but if im mixing two mh too 3 hps would it be better to go more of a blue like a 6k mh that has a little less red spectrum over a 4k?

[Speed of green]

You may be at the point of diminishing returns with your current watts/sqft.

That said my buddy swears by his 1000w MH parabolic hoods. He turns them on the last three to four weeks. They are positioned in his aisles.

since you are just trying to add some spectrum and not so much intensity i think 400's or 600's would be fine.

Also look into LEC's They are supposed to be the best spectrum people are crushing it with those.

[growingcrazy]

I like to run 1 mh with 4 gavitas, generally.

What are you running for veg? If you put a flip relay on your veg you can run a mh in flower during the off time in veg.

I have been doing this with success for a while. Plants also seem to like the simulated orange dusk/dawn with the brighter white in the mid-day. Just like nature...

[MJINC]

You could try hanging four vertical 400W/600W MH bulbs in the rows botween your Gavitas

[Floridian]

If you could work in 1K parabolics when flowering,I use the vertizontals old school I know,they had been responsible for a major increase in yield though.I had to stop and will be starting again in the next couple years but I'm leaning towards DE vertizontals which are relatively new.I may be behind the times here but those unlensed 1K horties just seem to toally kick ass if you can keep your temps controlled.Who knows though LED's seem to be so promising

[DocTim420]

If it were me, I would investigate the UVb spectrum (which is greater in MH lamps and far less in HPS). I subscribe to the notion that last few weeks before harvest a high dose of UVb (say in the 10k Kelvin neighborhood) increases trichome density and improves flavors. Also, plants hit with high UVb (around 7k Kelvin) during the first few weeks after flip show an increase in both girth and leaf canopy.

This is a 600w MH 10k I use for the last few weeks before harvest https://www.1000bulbs.com/product/88...MPS60010K.html

And the 600w MH 7.2k I use for the first few weeks after flip https://www.1000bulbs.com/product/11...MS6007200.html

Plantmax data sheet (very interesting) https://a89b8e4143ca50438f09-7c1706b...pdf?1482944613

Something to think about.

[Floridian]

Do these new LED's contain any UVB light?

[DocTim420]

Originally Posted by Floridian

Do these new LED's contain any UVB light?

That is my understanding--but not all LEDs are created equal. And, just a reminder, the naked eye can not see UVb (which means the light my be on--but you may not be seeing anything...or visa versa).

The welding supply store (where I pay $10 for CO2 refills) sells eye protectors that welders use to block the UVb spectrum. Whopping $3; hate to be blind at 100 years young, lol.

[mushroombrew]

I have better luck with 10K finishing bulbs for 10-14 days. Then a mixed spectrum.

Solis tek makes a DE. Maybe buy a couple and try them out. Before you add a bunch of MH?

Unless you use light movers it's hard to get a true mixed spectrum.

I think you're at about 42W/sqft? Check my Calcs?

I like to be over 60W/sqft. So maybe you do want some extra MH's for extra watts

Maybe that's why your buds were twice the size with the 1000W MH? Because your overall watts were not maxed out; not because of the mixed spec?

[DocTim420]

Amen to the 10k finishing. There are 1k bulbs but I prefer using 600w for my UVb source, especially in my perpetual garden. IMO, the benefits are:

1. A pair of 600w has better coverage than a single 1000w lamp.
2. The 600w lamp must be closer to the plant canopy thus concentrating the UVb spectrum to the targeted plants--not the neighboring plants. If the UVb source was from 1000w then the lamp would higher and a greater number of unintended plants would receive UVb sooner than desired.
3. Price is cheap, compared to the alternatives. My electric panel can not handle the increase 600w to 1000w for two banks of lights, nor will the current AC setup. Hmmm, new sub-panel, new ballasts, new AC for what??--a constant battle to prevent plants from getting hit with UVb at the wrong time? Nahh, the 600w lamps work perfect for me; their perceived weaknesses work to my benefit.

BTW, my mostly organic custom peat blend garden pulls a harvest every week or so; each plant averages just over a 1/4 pound of manicured buds. So yeah, do investigate which specific light spectrum you want, when and how long; it works for me. Imo, it certainly is better than doing what most everyone else is doing: MH (4k Kelvin) for vegetative growth and HPS (2-3k Kelvin) for flower/fruiting growth.