Scrog Waterfarm Grow

[onthe420train]

This is true, both are good for all stages of growth but flowering and budding require more red light.

metal halide has a better spectrum but lower intensity, therefore lower canopy penetration and coverage. Also most metal halide are lacking in red and a lot of metal halide growers have airy buds as a result of that and other factors.

 

[therootsofpositivity]

Ceramic metal halides I just heard of them the other day Propa Gator. I have actually been asking around if anyone knows anything about them. No one I know has used them or even knew what I was talking about! I haven't had time to read any grow journals with them yet. I will be really interested to try them when they come out in vertical 600w (as I know come summer will be upgrading to air cooled hoods). I think for my area three 600w would be more than enough and probably better light distribution that two 1000w. I really want to try and get my power consumption down as well. I would be hesitant to cover a 4 by 8 canopy with three 400w.

 

[Propa Gator]

Not Metal Halide. Ceramic Metal Halide by Phillips: Ceramic Metal Halide Fact Page ~ Advanced Technology Solutions, LLC
My buds are not airy, fluffy nor lacking in weight. They are very densely trichomed.
I'm using a 250w CMH on a cheap magnetic HPS ballast.

 

[therootsofpositivity]

One could try as well a combination. If there is something to just having a ton of red light maybe like two hps and a CMH in the middle or two CMH and a HPS in the middle. Again I think there is subtleties in spectrum and intensity that aren't well understood, or at least by me.

 

[therootsofpositivity]

Aren't CMH better on magnetic HPS ballast. I read you weren't suppose to use them on digital ballasts.

 

[onthe420train]

Yea I've read about ceramic metal halide.... same thing as regular mh, cmh also has a lower measured intensity than hps.

I think you use regular magnetic hps ballasts for them. Like sunpulse digital mh.

the peak wavelength of HPS is also closer to the peak needed for chlorophyll, while the peak on CMH is closer to unused light.

 

[therootsofpositivity]

I have not looked into the spectrum of CMH so can not comment on it. I do feel that without tests we can only guess as what is best. Yield is important and I think one thing we focus on as it is the one thing we can all easy compare. However I would like to see actual data on metabolite composition of plants grown under different lights. We could then see what timing is optimal to produce a high yield with optimal metabolite composition for our particular needs. Does ultrasontics sunpluse 10k bulb really pack on the trichomes? Is Propa Gator getting the cannabanoid profile optimum for the effects he desires with a CMH? I think without proper test all we have to go by is guess work. All I can say is if someones happy with the setup they have, the yields and quality they get, then that is the best system for them. It is always good to watch what other people do as you will always learn something.

 

[therootsofpositivity]

Just wanted to update about how much food the girls are eating. I put in 30L of water and 10g of 5-11-27 and 7g of calcium nitrate. There is less water in the system now than when I topped it up and the ppm are lower! So they have eaten over 17grams of food! That is crazy when you think how small a portion of the dry plant these nutrients compose. I am getting excited and hope the girls keep eating like this for another 2 weeks! I am not adding anymore Epsom Salt or mono potassium phosphate. I feel they have enough phosphorus and Mg and sulfur. I really want to not over due it with Mg and Sulfur as I have been told be a few old time growers that Mg and sulfur really produce a bad product. Anyone else agree with this? Signs of powder mildew. What do people like to use to control PM during flower? How is potassium bicarbonate? I just don't want to use anything that damages the pistils. Thanks in advance for any advice. Always really appreciative.

 

[Propa Gator]

Bicarb can kill it, but you need to get your humidity down and your air ciirculation up or it'll be right back like the Terminator!

 

[onthe420train]

yea something that will lower the pH out of the mildew's range then evaporate away I forget what people were using... lemon juice spray or...? something in the howtogrow or the faq has info about it.

 

[therootsofpositivity]

Ya Propa Gator I think the problem is condensation when the lights go off. During lights on RH is only like 25 to 30. I am continuously venting the room but I know the temps drop quit a bit at night and am sure that is increasing the RH. Still working on getting environmental controls in there. Just hard to move around with the room packed with flowers! Definitely going to be upgrades for the next grow. Reading Papa Green's grow and wish I could get everything automated!

Now from what I read you want to increase pH. I have high pH water so I am going to spray that and a bit of potassium bicarbonate. Hopefully this will make the environment less hospitable for the PM.

 

[onthe420train]

maybe it was baking soda...

 

[onthe420train]

Ah, potassium bicarbonate is baking soda. Google to the rescue!

 

[therootsofpositivity]

All the little spots of Powdery Mildew are gone so hopeful that the potassium bicarbonate worked. Again the girls under the china hat are just not filling out. Tons of bud sites, growth looks great but just not filling out. It is going to be the first thing I am going to replace once this grow is finished.

 

[onthe420train]

Thats a bummer dude yea I bought one of those with a 1kw light one time and used it once before skippin it off to the next grower for cheap. then had a cooltube but I really think the parabolic gull wings are the best if you aren't somewhere like texas.

 

[ultrasonic]

Ah, potassium bicarbonate is baking soda. Google to the rescue!

Sodium Bicarbonate is actually baking soda... potassium bicarb is used IIRC becuase the sodium interfers with the plants nutrient levels.

However, the sodium issue could have to do with using bicarb to adjust PH in a nutrient solution.

Wikipedia: Potassium bicarbonate is an effective fungicide against powdery mildew, allowed for use in organic farming.

 

[therootsofpositivity]

quick little fact. When people say plants don't use/see green light in fact only about 20% of green light is reflected or transmitted and is enough to cause plants to be green (Taiz & Zieger 1998) if you want full reference I can get it for you.

 

[Propa Gator]

Yes please, access to the full document I want. I suspect several findings there to be significant.
Learning stuff via the scientific method means never having to say you're sorry.
You can offer fancier alibis.

 

[ultrasonic]

quick little fact. When people say plants don't use/see green light in fact only about 20% of green light is reflected or transmitted and is enough to cause plants to be green (Taiz & Zieger 1998) if you want full reference I can get it for you.

It depends on what exactly you mean by "green light". Every type of green light will have light within it in other spectrum: it's just not nearly intense enough to a) be seen or b) be used by the plants

Alot of people don't realize the -industry standard- for a "dark night" in a hydroponic crop will allow you to read a book. A little bit of light, does not, has not, or ever will force a plant to go hermie. The idea of a green light is that it provides enough brightness (that we can see) that the plants can't see most of. Plants need a particular amount of light energy for photosynthesis to occur (plants don't start photosynthesizing until a few minutes after lights on)

I also have access to that article: printed in a recent hydroponic magazine. Not saying that what you're saying isn't correct: It very well could be. But you and I don't know "what" 20% is reflected back. It could be the 20% with 98% of the light energy, which, if it's a green light, would sound correct (it's green because it's most intense in that spectrum). Light spectrums are a very advanced thing, and i've come to learn it's just one more thing that advertisers can use to provide products to this new "hydroponic revolution". Kavin, Lux, Par, Lumens, foot candles, microseimens... AHHHH!! It's just like computer monitors and this whole dynamic contrast ratio fiasco. They're just there to trick people into making quick uninformed decisions: they make humans feel good... makes us feel like we're understanding things more. It's all very psychological.

At the end of the day, i've followed about 20 journals in my 5 years around here that used green illumination when working at light. Not one issue: that's proof 'nuff for me.

I'll be keeping an eye on your PM situation! Have you considered a sulfur burner? Love your setup man!

 

[onthe420train]

Kavin, Lux, Par, Lumens, foot candles, microseimens...

well Kelvin is temperature absolute zero scale, just Celsius + 273.15
Lux is a measure of luminous flux aka intensity which diminishes proportionally to the inverse cube of the distance from the source.
Lumens is a number used for man-made light sources to measure their outputs in relation to other man-made light sources.
Foot candles is the universal and more scientifically acceptable light intensity measurement.
Microsiemens is just a conversion of electrical conductivity. EC*1,000 gives you the microsiemen count of nutrients. Or 0.5 conversion ppm*2.