I'm trying out CMH

HayStack

HayStack

Well-Known Member
So the other day I ordered at 315 watt CMH with a 3100k Philips bulb from Grow Co. I've never used CMH before, but I have heard a lot of good things about them. My current grow looks like it's going to be a nice grow, but the lower buds just didn't get any light and you can really tell by just how tiny the buds a little lower down the branches are. I'm hoping that adding one of these to the lighting will make a difference. If it works well, I may just get another 315 and remove the LED's all together.

If anyone is running CMH lights, let me know how well they work. Are they worth the investment?
 
HayStack said:
So the other day I ordered at 315 watt CMH with a 3100k Philips bulb from Grow Co. I've never used CMH before, but I have heard a lot of good things about them. My current grow looks like it's going to be a nice grow, but the lower buds just didn't get any light and you can really tell by just how tiny the buds a little lower down the branches are. I'm hoping that adding one of these to the lighting will make a difference. If it works well, I may just get another 315 and remove the LED's all together.

If anyone is running CMH lights, let me know how well they work. Are they worth the investment?
Click to expand...


HS,
You have seen my grows and I use 315's. I have use LED's and HPS and neither compares to the 315.
JMHO

GR
 
gr865 said:
HS,
You have seen my grows and I use 315's. I have use LED's and HPS and neither compares to the 315.
JMHO

GR
Click to expand...
I have seen your grows. That's what made me get this CMH. It got delivered yesterday evening and I installed it the moment it was dropped of at my door. My tent only had about three hours of it before the lights shut off for the night. But from what I can tell, there is a huge difference with the light penetration. I only have two weeks of flower to go for this crop. But I'll be using it fulltime on my next crop. I might even buy another one. Unfortunately, I have to work today, so I can;t standby and watch the temp. Hopefully it doesn't go up too much. But it was at 80 degrees when I left the house this morning. That was after the light had been on for a little over an hour. I left the bottom of the tent door cracked a little for more air.

I'll post some pics when I get home this eveninig
 
My ballast are remote outside the tent with fan blowing on the, so the heat isn't a factor. When running one 315's I had not prob with heat at all. Two 315 I would have the fan for the exhaust filter on two max setting. When I added the SS400 LED I have to run my blower on high and and turn on the a/c for the room. That gives me approx 975 watts of light, which also puts out some light heat. When we run the LED in the future, for early veg or to help finish the plants I think I will build something to move the heat directly into the exhaust filter.
Over all, if I had not let the plants grow into the light, I think the plants handled the heat very well, high of 83 and low of 64 , but on average it's 79 and 66 degrees.
 
gr865 said:
My ballast are remote outside the tent with fan blowing on the, so the heat isn't a factor. When running one 315's I had not prob with heat at all. Two 315 I would have the fan for the exhaust filter on two max setting. When I added the SS400 LED I have to run my blower on high and and turn on the a/c for the room. That gives me approx 975 watts of light, which also puts out some light heat. When we run the LED in the future, for early veg or to help finish the plants I think I will build something to move the heat directly into the exhaust filter.
Over all, if I had not let the plants grow into the light, I think the plants handled the heat very well, high of 83 and low of 64 , but on average it's 79 and 66 degrees.
Click to expand...

I'm kind of wishing I would have gotten a CHM with a removable ballast. Mine is wired straight into the light. After harvest, I might take it apart and see if I can remove it and mount it outside too. I saw a couple youtube vids of mounting the ballasts outside. But of course that was after I ordered mine. Ha!

Unfortunately I got home shortly after the lights went out for the night. But it was 75 degrees when I got home. I'm pretty sure the tent did not get much over 85 or so. That's fine by me. I'm still a noob at indoor growing, but I've had a lot of outdoor grows and I know they can handle the heat as long as it doesn't get over 100 degrees. Over 100, these plants start to stress out a lot. But I think they love it in the mid 80's. I might be imagining things, but I'd swear the buds got fatter after a couple hours yesterday and all day under the new light.

And thanks for the CHM tip! I think it will make a huge difference.

20180326_205314.jpg

20180326_205314.jpg


20180326_205258.jpg

20180326_205258.jpg

 
Update:
So I've had my tent with the new grow under two 315 watt CHM's for almost a week now. And I have to say that I think these are the best lights I've used so far. The growth is unbelievable. Here are a couple pics.

This was on Tuesday.
20180508_094540.jpg

20180508_094540.jpg


This one was taken this morning. I'm kind of blown away with this growth
20180510_180120.jpg

20180510_180120.jpg

Thursday 05-10-18
 
How far away do the lights have to be? I’m wondering how much it would cut into my headroom. And do you think these same lights will perform as well in flowering?
 
Weaselcracker said:
How far away do the lights have to be? I’m wondering how much it would cut into my headroom. And do you think these same lights will perform as well in flowering?
Click to expand...

I've kind of been experimenting with the distance of the light. When I first installed mine, they were about 30" or so. Now that the plants have grown and I have lowered them a little bit, they are only about 20" from the lights. Maybe a little less. So far, all is well. But if they start showing signs of too much light I'll raise them back up.

I am expecting the lights to work better than the LED's I used last grow and way better than the 250 and 300 watt CFL's I used on my first grow.The amount these plants seem to grow on a daily basis is really good. Better than I have seen with any of the other lights I have used. I'm pretty sure once they go into flower, all hell is going to break loose. :cool:
 
I have a Sunsystem 315 LEC. They are great for high THC resin potent plants. The only problem I had with mine is the heat. They give of infa red so you have to keep your plants cooler than with energy efficient COBS. In the summer you'll have to use air conditioning or unzip the tent all the way. May burn off some of the turpines.

Now I'm growing with a Migro 400. Buds are always sweet smelling with not such a strong odor. Buds are similar in size. I don't know yet if the potency is as high as the LEC but it is more than good enough.
 
I'm consistently impressed with these lights. The daily growth is better than anything I have used so far. Daily and weekly trimming is mandatory.

This is back on the 8th of May
20180508_094540.jpg

20180508_094540.jpg



This is from yesterday may 26th
20180526_123407.jpg

20180526_123407.jpg

 
CraZysWeeD said:
Interesting tread! I have looked at these lights and wondered how good they are. That looks amazing. Is the light hotter than hps?

Will definitely check in to see this grow through!
Click to expand...

I have never grown with HPS lights. The only other lights I have used were LED's and CFL's. But the CMH's are a little hotter than the LED's and the CFL's for sure. At first, I would say they raised the temp about 10 degrees over the LED's. But I put one of the CMH ballasts outside of the tent and that helped by maybe five degrees. I will probably mount the other one outside as well, so hopefully it will be just a few degrees warmer than the LED's.
 
Weaselcracker said:
Thanks for the reply. Will you be around somewhere to let us know how it goes, or update this thread? That would be great.
Click to expand...

I plan on keeping this tread updated regularly. I'm hoping to get a better harvest than my last LED grow. I got about 18 oz. out of that grow. I wonder if 20 oz op more is possible with these lights. Stay tuned.
 
You maybe wanna consider mounting them in cooltubes. That did a lot for me when growing with hps in tents. Got a 10C drop instantly.

You are the first I know of to try these babies out. Where I live they are veeery expensive, just the bulb is like 200$ and another 200$ for the ballast and fixture. My question when I saw these lights was do they run on hid ballasts? Like the hps and MH can?
 

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