Spectrum Change Questions

[killfrenzi]

I have a 1000w switchable ballast that I am currently running 18/6 under 400w Mh.... And I was wondering if there are any benefits from changing spectrum between a 400w Mh and a 1000w Hps during Veg and/or Flower.


Any advice?

[CovertCarpenter]

... if you're running a 400w MH, you're currently getting around 30,000 to 40,000 lumens, and prolly round 4100k colour temperature. Great for vegging.

If / when you switch to the 1000w HPS, you'll be getting around 140,000 to 150,000 in the same space (and at a nice 2000-2100k colour temperature; better for flowering), so I'd make SURE you have good ventilation, and some headspace for the flowers to explode in :)

And a good set of sunglasses to wear while gardening ;)

[killfrenzi]

Already on the sunglasses part. Ihave tested the HPS its super bright. I am doing the LST method and have plantey of head space.

Thanx, but what about changing the spectrum on the same light schedule? What would this pose to the plants?

[CovertCarpenter]

...that you need a 'blue-r' light during veg, to help prevent too much stretching (and using Bushmaster can help to ameliorate this)...

and a 'redder' light during flowering, to help promote budding...

But for sheeeah powah, it's hard to beat a 1000w HPS under any conditions :) The only thing that does, and for efficiency alone, is a 600w HPS, tho it has nowhere near the lumens of the thou. If you wanted to help flesh out the spectrum of the HPS and just use it for the whole show, put a few CFLs in there of 4100k or 6500k.

I don't think you'll see many (if any) probs, tho you may have to keep the thing 24" to 36" away from the top of the canopy, to avoid cooking the lil girls (or put mega-fans on it)...

[killfrenzi]

I have an 18" oscilating fan on low and a swamp cooler on low that keep the temp steady between 74 during day w/ 44-58% humidity, and 66 with 32% humidity at night; I only have (1) 6" inline fan hooked up to my enclosed light fixture that is pulling heat off the light and whatever else out the room. I plan on purchasing an other 6" and 8" inline fan to hook up to my hommade carbon filter and for better exhaust when I start flowering. I think I might Change spectrum to Hps 1-2 weeks before I flower, just to pre warn the plant that it is almost fall.

Thanx for the advice and any other advice is always welcome

:thumbsup: