315 cmh vs led

[beercan]

So i think im to the point that i need to change bulbs in my 315w cmh fixtures, pretty expensive bulbs to be changing every year or so, my last run yeilds were way lower than expected, i also run 260 w leds from hlg as supplemental lighting to the 2 315's in a 4x4, so should i go all led or change bulbs in 315s? I was looking at a timber fixture or perhaps buying a few more 260 w hlgs

 

[bk78]

That a lot of light for a 4x4. Doubt the yields were less due to the lights. Other issues at hand imo.

 

[beercan]

That a lot of light for a 4x4. Doubt the yields were less due to the lights. Other issues at hand imo.

Buds are getting fluffier

 

[Rurumo]

so you're running 630 watts of cmh plus how many hlg 260 watt fixtures in a 4x4?...that seems way overkill. What else have you changed...strains?

 

[beercan]

I should have worded that different lol, im running 2 315 cmh and 1 260 hlg led, i added led when bulbs were a year old in cmh fixture's they run non stop

 

[beercan]

Same strains every time

 

[Dape Green]

I changed my 315’s at 1 yr or so, that’s when I felt I started losing density as well. So at 300$ in bulbs per 12-14months it made the higher priced LEDs nut seem so crazy. I’m on my first run right now with a HLG scorpion and am blown away. I mean there is zero shade in there.

 

[Norml56]

85% PPF maintenance at 20,000 hr. I only run my CMH in flower so I'm only changing them every 3 years. 15% reduction in light at 20,000 hours is fairly minimal IMO. $160 for 2 bulbs so about $50 a year in bulbs is totally doable for me.

 

[GBAUTO]

That a lot of light for a 4x4. Doubt the yields were less due to the lights. Other issues at hand imo.

Agreed.
The pair of 315's with the HLG should generate over 1900 umoles ppf.
That's more than enough light for a 4x4, that's about what most folks use over a 5x5.

 

[Gemtree]

I've had a igrowtek cheapy bulb off amazon going for 6mo now and seems good for half the price

 

[MidnightSun72]

Buds are getting fluffier

What are your temps? Fluffy bud = hot room

 

[beercan]

72 off 80 on

 

[bri77]

Is that leaf temp or room?

 

[Norml56]

Are these Genetics you've run in the past with much better results? I've never experienced a change in bud quality or yield for the worse, and I'm also running CMH with HLG QB boards. I wouldn't ditch the CMH for all LED unless you are having temp problems. The 2 lights really compliment each other IMO

 

[GrownAtHighAltitude]

You'll spend more on electricity heating an all LED space up to 80F+. Also, the CMH gives off UV that the LEDs don't, so you'll need to supplement that too. (Solarcure, etc).

Phillips bulbs engineered for longer usable service life with less degradation.

 

[beercan]

Yes same strains

 

[Norml56]

You'll spend more on electricity heating an all LED space up to 80F+. Also, the CMH gives off UV that the LEDs don't, so you'll need to supplement that too. (Solarcure, etc).

Phillips bulbs engineered for longer usable service life with less degradation.

The UV output on CMH seems to be debated quite a bit. I've seen tests done by growershouse that shows UV output but others say that the glass used to make the CMH stops the UV. I know that Hortilux makes a special CMH bulb that they claim allows the UV.

 

[Norml56]

I should have worded that different lol, im running 2 315 cmh and 1 260 hlg led, i added led when bulbs were a year old in cmh fixture's they run non stop

I'm assuming by non-stop you mean that you Veg and flower in the same tent. Is that correct? You should caculate how many actual hours the bulb is on.

 

[beercan]

I'm assuming by non-stop you mean that you Veg and flower in the same tent. Is that correct? You should caculate how many actual hours the bulb is on.

Yup

 

[Norml56]

Based on a rough guess of 2 months veg and 10 weeks flower that is 2280 hrs of bulb on. About 6,840 hours a year. I would personally run that bulb for 2 years before replacing. You are still well below the 20,000hrs at 85% PPF Maintenance. If you are replacing every year you for sure aren't seeing a drop in quality/yield because of a worn out bulb.