how close to hang lights please chime in

[Dizzworth]

Sooo my whole growing life i always though you wanted to get the light as close as you can to the plant without hurting or burning it. I am 4 weeks into flower on my lemon alien dogs and i was curious about some light issues. I noticed some of the nugs that are directly under the light are growing a bit more stringy that the ones a bit outside of the light. The plants are green and lush but the ones under the lights are not stacking as i thought they would. What are your opinions on how close to keep thousands? i do not vent my light so i hear the rule of thumb is 2 feet? Please chime in

 

[GR33NL3AF]

By stringy, you mean fox tailing? I would get more air movement to the canopy, probably raise lights to 30" and see if the fox tailing slows or stops.

 

[Dizzworth]

By stringy, you mean fox tailing? I would get more air movement to the canopy, probably raise lights to 30" and see if the fox tailing slows or stops.

thanks green and yes fox tailing..i do only have two 16inch fans in my 10 by 11 room and always though i might need more..i was around the range of 15-18 inches before so i raised them to 24 so hopefully it stops.

 

[Dizzworth]

bump

 

[DrRabbit]

bump

I use a couple of tests. Using a digital thermometer, I hang it's temp probe at the level of the canopy top. It really is a temperature issue. Also, if you can hold your hand with the back exposed to the light at canopy level for around 60 seconds without feeling warmth, you're probably okay.

Airflow directly beneath your lights also will allow you to move them closer to the plants. Using vented hoods and with horizontal airflow directly beneath the housings, I've positioned 1,000 watt HPSes within 18 inches or so of the plant tops.

Why don't you vent your lights? It's the easiest way to eliminate heat. It certainly is the most cost-effective way to cool your room.

 

[woodsmaneh]

Sativa's like to foxtail and most strains that do foxtail have some Sativa in them. Hitting your plants with a booster in flower at week 6 will also bring on foxtailing, stuff like Overdrive and H&G Shooting Powder, so any PK adder will trigger it if your strain has it in it.

The only test for heat with lights is the hand test ^^^^use back of the hand on the top of the plant, any heat move it up. I have a digital but my hand is not battery powered and never fails or lies. You can see some foxtails on these plants

 

[DrRabbit]

. . . use back of the hand on the top of the plant . . . .

Genius! This is about as easy and telling as it gets.

I depend more on digital thermometer because airflow in my tent is best assessed when zipped closed, which doesn't give an old fat man like me much maneuvering room on the inside!

 

[Cort]

I keep 2 cheap remote probe indoor temp/outdoor temp/hygrometer units inside the tent. Probes at canopy level in 2 spots around tent. One directly under the light, other in the corner least likely to get air flow (furthest away from intakes, away from fans/filter)

Agree on more air, cooler temps for canopy = less foxxy.

 

[ttystikk]

All this is great advice. I used to run a light rotator, and as long as it kept moving at its stately pace of one turn every 3 minutes, I could let it get within 12-14" of the tips and if never hurt a thing.

A hood that is designed to be sealed and vented is going to be very hot underneath. If you aren't going to vent your hoods, get reflectors that are best for YOUR APPLICATION. Adjust-a-wings would be an excellent choice.