how much light should/can i use

[outsiders]

hi im using a spider farmer sf 2000 grow light.

its in a 2.5x2ft with reflective walls

i only have one small plant in veg. i see it to be a big waste of electricity to have it running on full right now and hung high

what can i turn it down to yet still have a acceptable par reading hung at 18 inches

it runs at about 200watts and i have it hung at about 30 inches. i was thinking turn it down to 100 watts and hang it lower??? like 18 inches then put it back on full for flower

second question is does this light lose its power efficiency to light output when turned down or does it scale down with the less power use

 

[coreywebster]

If you dim it your reducing the current which increases the efficiency but lowers the output.

I would base the decision on the temps in there, if you dim to 100w your cutting your heat down so see what happens. If you go lower than 80f then its detrimental to turn it down if you then have to heat it back up by other means.

 

[PadawanWarrior]

hi im using a spider farmer sf 2000 grow light.

its in a 2.5x2ft with reflective walls

i only have one small plant in veg. i see it to be a big waste of electricity to have it running on full right now and hung high

what can i turn it down to yet still have a acceptable par reading hung at 18 inches

it runs at about 200watts and i have it hung at about 30 inches. i was thinking turn it down to 100 watts and hang it lower??? like 18 inches then put it back on full for flower

second question is does this light lose its power efficiency to light output when turned down or does it scale down with the less power use

You can download a free lux app for your cellphone to give you an idea of the light intensity.

If you really want to know the actual draw of the lights when adjusting get a KillAWatt meter.

And LED's are usually more efficient if ran at a lower wattage.

 

[outsiders]

You can download a free lux app for your cellphone to give you an idea of the light intensity.

If you really want to know the actual draw of the lights when adjusting get a KillAWatt meter.

And LED's are usually more efficient if ran at a lower wattage.

i have a KillAWatt meter. i tried one of them apps couldnt get any to work on my phone. its a old phone

i was going to look for a cheap par meter if cheap is even a thing when it comes to them

best i have to go on right now is looking at the provided par reading on full then dividing it by half and guess thats what its outputting. would a par reading of around 400 be enough for veg . i have been told you need around 900 par to flower and apparently this light outputs that on full at 18 inches

 

[outsiders]

If you dim it your reducing the current which increases the efficiency but lowers the output.

I would base the decision on the temps in there, if you dim to 100w your cutting your heat down so see what happens. If you go lower than 80f then its detrimental to turn it down if you then have to heat it back up by other means.

the light stupidly hot running on full but it doesn't add much heat in the grow space as i have good air exchange so for me i dont think turning it down will make much temperature change

 

[coreywebster]

the light stupidly hot running on full but it doesn't add much heat in the grow space as i have good air exchange so for me i dont think turning it down will make much temperature change

It will make some, but you can add a speed controller to the fan to reduce the flow to counter it.

You probably only need it on 160-180w in full flower at 18" and half that in veg. Though if you can run more in veg without problems then go for it.

The board will be hot because its just a plate rather than a heatsink, a fan blowing across it makes a big difference, obviously most heat from LED goes straight up rather than be radiated down.

 

[outsiders]

It will make some, but you can add a speed controller to the fan to reduce the flow to counter it.

You probably only need it on 160-180w in full flower at 18" and half that in veg. Though if you can run more in veg without problems then go for it.

running it full isn't a problem im just cheap and don't want to use/pay for more power then i really need. arr if you're saying plants will grow faster in veg with more light then im a leave it on full. im not looking at making the plant grow slow i was just looking to save a few dollars

 

[coreywebster]

running it full isn't a problem im just cheap and don't want to use/pay for more power then i really need. arr if you're saying plants will grow faster in veg with more light then im a leave it on full. im not looking at making the plant grow slow i was just looking to save a few dollars

Plants typically will have more growth with more light, but you have to be careful with LEDs like these, I struggle to be over 15w per square foot in veg and i have to add a small heater and keep light hours less to make it work without light stress. (don't have the option to raise the light in that tent)

Seen it a lot with other LED growers, but then there are those who have no issues running higher par and seemingly the same environment.

See how it goes for you.

 

[twentyeight.threefive]

I ran mine on full at about 30 inches through veg. I didn't care enough about saving money to have to remove the driver multiple times to adjust the output. Sorry I know this doesn't really answer your question, it was just my thought process on deciding whether to adjust the wattage down.

 

[outsiders]

I ran mine on full at about 30 inches through veg. I didn't care enough about saving money to have to remove the driver multiple times to adjust the output. Sorry I know this doesn't really answer your question, it was just my thought process on deciding whether to adjust the wattage down.

fair enough i could see it being a pain if getting to the light is hard. it should be mounted the other way around

 

[outsiders]

Plants typically will have more growth with more light, but you have to be careful with LEDs like these, I struggle to be over 15w per square foot in veg and i have to add a small heater and keep light hours less to make it work without light stress. (don't have the option to raise the light in that tent)

Seen it a lot with other LED growers, but then there are those who have no issues running higher par and seemingly the same environment.

See how it goes for you.

if more is better ill leave it with more then

 

[twentyeight.threefive]

fair enough i could see it being a pain if getting to the light is hard. it should be mounted the other way around

Or at least have a remote knob for adjustments! I'm completely happy with the results at full power though for sure.

 

[323cheezy]

I wouldn’t go full blast till flower ... your plants can only grow so much in one day.
I did know this guy however that did a 3x3 with a 1000 watt hps ac. He had a 300 page journal on here. His buds got so swell and dank shit got to his head and he went off the deep end .. lol but true story his buds were dank af but they molded a bit in his last weeks cause he failed to realize how dense they would get .

 

[flattylfc]

If you dim it your reducing the current which increases the efficiency but lowers the output.

I would base the decision on the temps in there, if you dim to 100w your cutting your heat down so see what happens. If you go lower than 80f then its detrimental to turn it down if you then have to heat it back up by other means.

Does it matter I my temps fluctuate during the day and night they go between 20c and 25c they change regular

 

[coreywebster]

Does it matter I my temps fluctuate during the day and night they go between 20c and 25c they change regular

No if you mean 25 lights on then 20 lights off.

I would want a couple more degrees lights on , like 27+ and not let it go below 20 lights off, though they will take it.