What’s up guys. I was wondering if anyone has any input on whether or not a 315w cmh would be too much light for a 2x4x5 tent? I used to run a “600” vipar with no heat issues and never an issue on light height but I want to upgrade my light. Now I’m thinking a 315 would flower much better than the blurple but I’m worried it’s gonna be too much light for the space and cause more problems than benefits. Any advice on which route I should go? Or would a 250w mh/hps perform better? I even thought abt 2 150w mh/hps. Just need some input before I go spending money
315 cmh vs led
- Thread starter Chip_pz
- Start date
Rocket Soul
Well-Known Member
You can also run a cmh hotter than hps, we had no issues at 28-30°C.
2 foot samsung sedstrips are also great for that space, ledgardener has a few setup options on his site. 240w is all you gonna need.
2 foot samsung sedstrips are also great for that space, ledgardener has a few setup options on his site. 240w is all you gonna need.
I’m back and forth between the 250 mh/ hps set up and the 315. I’m thinking I’m going w the 315. And I had 1 of the 600. Ran abt 15in in veg and abt 6-8 in flower. I’m upgrading bc the intensity just isn’t enough. The problem running it so close in flower is the footprint becomes substantially smaller any closer than 12” but the intensity suffers as well.
So u think 5 foot is plenty of headroom for say a 2 foot canopy w a 315?
raratt
Well-Known Member
You can always top them, do LST or SCROG to keep the tops low enough. Height should be 1-2' off the plants depending on how they react.
coreywebster
Well-Known Member
A 315 is designed to best cover 3x3, 9square foot. So its defo not too much for 2x4 but it does lend itself better to square tents.
A 250w hps would not be better, although 2x 150w hps would give better spread of light but not as nice a spectrum, plus a 315cmh is good for both veg and flower no matter which bulb you use.
A 250w hps would not be better, although 2x 150w hps would give better spread of light but not as nice a spectrum, plus a 315cmh is good for both veg and flower no matter which bulb you use.
Are you running exhaust thru your hoods? Was thinking of getting a hood I can vent my exhaust thru and kind of use the fixture as my exhaust port and light source
no pal exhaust is oversized though 8inch but ony have it running at 20% or so. i'm in the uk outside temps are quite reasonable for this time of year. if anything i'm slightly worried if any more drop in temps.
StareCase
Well-Known Member
I hear ya. The 1 600 Reflector wasn't enough so I got a second one. Two of them worked well in the 2 x 4.
I was going to flower them with both lights @ 12" above a SCROG - but I was wondering when you went to 15" above the canopy for veg? I just transplanted a 4" clone and have the light roughly 20" above which I was going to keep there until she started to show some bulking up with branches and fans. Do you think that it's still too little of a lady for me to lower the light to 15" now?
In a year or so, it is anticipated that a lot of "der kinderjunk" ( made up word - don't flame me for incorrect German ...
) in our storage area will go to der kinder. A 4 x 4 would go nicely in that vacated area. With the increase in footprint would come more powerful and less blurple lights. We'll cross that bridge down the road ...I started in a 2x3x4 with the 1 600. Never had a true exhaust fan and barely got by running mid to high 80s Fahrenheit the whole time. Upgraded to an actual tent with an actual exhaust and temps rarely ran over 81. Mostly mid to high 70s. Came to the conclusion that the light just isn’t enough to spread the 2x4 and give good enough intensity. Plus after using a blurple I’m now a non believer. Honestly HID is the way to go unless you dive into the diy world. I stay way too stoned to concentrate enough on that when it comes to pairing the right drivers with the right light to get the right power. But yea I pretty much started seedlings at abt 30 inches blue side only. Then when they started their 3rd set of true leaves I’d flip the red side. And slowly over the course of a week move it to 20 inches. Once she showed vigorous growth and more branches I would lower to 15. Although I would say you can probably run it closer. I find the closer you run the light in veg the closer the nodes stay together.I hear ya. The 1 600 Reflector wasn't enough so I got a second one. Two of them worked well in the 2 x 4.
I was going to flower them with both lights @ 12" above a SCROG - but I was wondering when you went to 15" above the canopy for veg? I just transplanted a 4" clone and have the light roughly 20" above which I was going to keep there until she started to show some bulking up with branches and fans. Do you think that it's still too little of a lady for me to lower the light to 15" now?
In a year or so, it is anticipated that a lot of "der kinderjunk" ( made up word - don't flame me for incorrect German ...
StareCase
Well-Known Member
Thanks Chip. ThunderCat has mentioned the inverse square law and the degradation of the light intensity hanging at the 22" - 24" range which seems to be recommended by most blurple manufacturers. This has me interested in lowering my LED's to 12" - 14" for all cycles and it's good to hear your confirmation. But I'll give it time to show more aggressive vegetative activity before I lower the lights.
I did a clone from a 15 day flowering mommy that, after a long 2 months, finally took off. 3 days after transplanting and taking to her new home, I cleaned out the weird shaped single leaves and remaining bud and have started some gentle LST on her. Today I have what looks like 4 newly sprouted seeds going upward with that nice vegetative green colour. Should be fun few weeks watching her fill out then weaving her through my netting.
I find that running the LED's with both VEG and BLOOM switches on from Day 1 also reduces the spaces between the nodes.
Yea really I just kept it as close as I could and still get the whole canopy covered as best I could. 1 was def not enough in a 2x4 for coverage. I’m done with the purple. It’s honestly a waste of time and money for me. I’d rather not grow than to grow w a purple again. I’m not even sure I’d waste the extra money in my light bill to use one for supplemental lighting.
Is there a difference in spectrum between a 150 hps and day a 600 or 1000?
coreywebster
Well-Known Member
Not that I know of, but different bulb manufacturers have slight variations and various types of dual spectrum of enhanced spectrums.
From what I understand a bulbs spectrum can change if its boosted or dimmed too.
There are probably a limited amount of companies that bother with say 250w or 150w bulbs in comparison to the many 600w bulbs available.
Gotcha. That makes sense.