Great point. Only wish they were a lil cheaper when I was in the market for ballasts...
Need to do a cost analysis and see if electric savings will justify. Gotta justify my new toys ya know.
how many watts per Sq foot
- Thread starter DrFever
- Start date
Great point. Only wish they were a lil cheaper when I was in the market for ballasts...
Need to do a cost analysis and see if electric savings will justify. Gotta justify my new toys ya know.
your saying 250 digi better than 400w mag ??
rangergord
Active member
No I have a 400 watt digital that grows better in my confined space when it is dimmed to 250 watts. In other words it can be a mistake to cram a big light into a small space in the hopes that you will have a better crop.
Not surprised in the least.
Shouldn't go higher than 72F for premium bud. Plants respond better to the proper lighting, when everything else is balanced properly as well.
Stay Safe!
Each growers room and ability is so different The effect of temperature on the rate of photosynthesis is little than on other processes. Very high and very low temperatures effect the photosynthetic rate adversely.Not surprised in the least.
Shouldn't go higher than 72F for premium bud. Plants respond better to the proper lighting, when everything else is balanced properly as well.
Stay Safe!
the rate of photosynthesis increases with the rise in temperature photosynthesis is doubled for every 10 C increase in temperature. In desert and C4 plants photosynthesis may run relatively at high temperature.
4. Respiration :
The rate of respiration increases with the rise of temperature up to a certain level, but beyond the optimum limit the respiration rate shows marked decrease. The rate of respiration becomes doubled at the increase of 10C above the optimum temperature provided other factors are favorable. In fact, respiration continues to increase after gross photosynthesis has reached its limitation by CO2 diffusion and enzyme kinetics. Thus the net photosynthesis is reduced
5. Flower Initiation :
In many crops low temperature is required for flower initiation. The phenomenon of acquisition or acceleration of the ability to flower by chilling / low temperature treatment is termed as vernalization.
I used to also believe perfect temps of 72 - 76 were needed for optimum growth cycles, and i think most issues growers are getting are heat stress from running hotter temps, stagnant air, poor ventilation or inadequate
But in all honesty raising temps 78 - 87 i have seen amazing differences in overall growth and yield could easily say by 20 - 30 percent and most importantly keeping relative temps around 68-72 lights off.
I find its less stress full for plants, to fast drops in temperatures lights off plant starts using its energy to survive maintaining root zone temps equal rather then sudden drops from lights off periods is the KEY
just walk into a green house and feel the heat ??? when you walk in. They look beautiful and healthy
Is it possible after 3 or 4 runs with my 250watt Eye Hortilux it is no longer effective? Seems like it doesn't even warm my hand and I thought it would burn it b4.
Pe@ce,
HymroD
L
longwaters
Are we talking room square footage, or canopy square footage?
1 year tops on a hortilux. But I stopped buying hortilux and now buy Plant Max and replace every run (2 months). $35 for a 1k hps. Not sure about a 250 watt.
D
DHF
I ran Krusty buckets at several locations for a decade with 4-600 watt eye-horti`s in the corners and a cheapass 1000 watt mh in the middle of an X light pattern with plants in a diamond pattern with 10 x 10 rooms for a total of 34 watts per sq ft with bare bulbs hangin and only 4 plants in each room.....and........
Pulled 2-1/2 lb dialed plants/10 lb rooms consistently for as I said......many yrs........but.......
When I was finally convinced to up the wattage to 50 per sq ft , my yields didn't go up per se , but quality and potency did since it was a strain I`d run for many many yrs , and knew her inside and out.........so........
Moral to the story is........This shit`ll grow under ANY bulb , but for optimum results and return on investment , efficiency and bottom line best quality end product by pullin and squeezing every gram yas can from a dialed strain , requires 50 watts per sq ft minimum IME........
Anything less and ......Your mileage may vary...but....with higher watts per sq ft more dialed environment comes into play with ambient temps and humidity levels to be dialed in further and again as stated above....Yields don`t increase with more watts per sq ft........especially without dialed environment....but....quality and potency do....WITH dialed environment......guaranteed.........anyways........
My 2 cents from all those yrs.......Good luck and....
Peace...DHF.....
.......
Pulled 2-1/2 lb dialed plants/10 lb rooms consistently for as I said......many yrs........but.......
When I was finally convinced to up the wattage to 50 per sq ft , my yields didn't go up per se , but quality and potency did since it was a strain I`d run for many many yrs , and knew her inside and out.........so........
Moral to the story is........This shit`ll grow under ANY bulb , but for optimum results and return on investment , efficiency and bottom line best quality end product by pullin and squeezing every gram yas can from a dialed strain , requires 50 watts per sq ft minimum IME........
Anything less and ......Your mileage may vary...but....with higher watts per sq ft more dialed environment comes into play with ambient temps and humidity levels to be dialed in further and again as stated above....Yields don`t increase with more watts per sq ft........especially without dialed environment....but....quality and potency do....WITH dialed environment......guaranteed.........anyways........
My 2 cents from all those yrs.......Good luck and....
Peace...DHF.....
.......Whoops... forgot to remember that I never flower at higher than 35-40% humidity.
Any time temps have gone over that... quality has gone down significantly at that humidity.. No clue at yield as I'm a personal grower and haven't weighed anything in years.
Stay Safe!
Thank you for confirming what I thought. My current run is shit and I could not understand why bottom growth is lush. (Due to my 48" flo add ons and 75mh supplement). I will check out the other brand too.
Pe@ce,
HymroD
Maybe it has been mentioned already in this thread and I missed it, but watts/sqft are really a poor marker...... 1000w of what? Which bulb? At what nm does it really pump out the photons? Red 630, 660 Blue 445, 452 ????? Do you believe the myth that green is not useable by plants?
Really, you should look first at picking a well tuned lighting plan that will utilize bulbs that emit photons in the correct spots and that will cover the entire spectrum and then go from there.... Years ago I started using the Philips 4k CMH bulbs in 400w and 250w over a 4x6 area. 1.5lbs was easy in this set up. 43.75w/sqft...... It had to do with good photon production in the correct nm points, multiple bulbs (points of light emission) and full spectrum. Dialed in environment and a good yielding strain. I could have loaded the area with more wattage and fought more heat load. Crammed in more plants and fought that battle, but it wasn't about watts! That is for sure.
It was a very efficient grow where KWH and my efforts required were considered.
Watts are like lumens. Worthless to plants.
Really, you should look first at picking a well tuned lighting plan that will utilize bulbs that emit photons in the correct spots and that will cover the entire spectrum and then go from there.... Years ago I started using the Philips 4k CMH bulbs in 400w and 250w over a 4x6 area. 1.5lbs was easy in this set up. 43.75w/sqft...... It had to do with good photon production in the correct nm points, multiple bulbs (points of light emission) and full spectrum. Dialed in environment and a good yielding strain. I could have loaded the area with more wattage and fought more heat load. Crammed in more plants and fought that battle, but it wasn't about watts! That is for sure.
It was a very efficient grow where KWH and my efforts required were considered.
Watts are like lumens. Worthless to plants.
In my limited experience, comparing results for myself with same strains, 60-70 watts per sq ft has given me significantly better quality compared to 35-40, with a fairly similar gpw yield. When considering the reduced workload from less canopy and less time trimming, and better quality bud, higher w/sq ft has been more efficient and rewarding.
There have been other past threads here on ICmag about this, and some very high watts per square foot grow threads, that have contributed to leading me towards a change of plan. I'm going to try low plant count horizontal, well pruned and LST'd plants under many overlapping lights, +100w/sq ft. If/when having heat problems, or a 'surplus' from veg space, watts per square foot could be lowered either by turning a light or two off or increasing the canopy/coverage area.
There have been other past threads here on ICmag about this, and some very high watts per square foot grow threads, that have contributed to leading me towards a change of plan. I'm going to try low plant count horizontal, well pruned and LST'd plants under many overlapping lights, +100w/sq ft. If/when having heat problems, or a 'surplus' from veg space, watts per square foot could be lowered either by turning a light or two off or increasing the canopy/coverage area.
ELuminated
Member
This turned out to be the best read I have found today. Thanks to all who leave such great info!
I will never let my root mass get cold, or measure my light footprint with lumens again.. Feels good to learn from people who understand and have passion. I am glad I found this forum.
I will never let my root mass get cold, or measure my light footprint with lumens again.. Feels good to learn from people who understand and have passion. I am glad I found this forum.
