How to know how much light is enough

[Bullfrog]

VPD vapour pressure deficit
NER nutrient element ratio
EC electrical conductivity

NER and EC is essentially the balance and concentration of nutrients

 

[Mellow oldfark]

kiss bro.

 

[Bear777]

For an average led with an overall spectrum between 2700-3500k, you can multiply your lux by 0.0155 to get PAR within a few percent...depending on your spectrum it can be anywhere from 0.0148-0.017. CMH is the most efficient at turning luminous flux to active radiation at 0.017, whereas lights with heaps of stark blues a deep reds will need a different coefficient.

At the end of the day, as bullfrog mentioned,It all depends on the plants metabolism and several environmental factors as well. Personally I run everything at 35k lux (550umol/s) over 18 hours for veg and 950umol/s over 12 hours for flower which give a DLI of 30-40 for the whole grow as I have a pretty steady environment.

At the end of the day "percentage X at distance X" don't mean much. Lux meters are cheap and convert to PAR easily, but the plants body language will do most of the heavy lifting.

I've been reading over the thread and I missed what does the abbreviation DLI stand for. I did end up putting the photone app on the wife's phone and tried it out quickly, looks like I will have to try it again after upgrading it to full spectrum.

 

[VinDeezle]

I've been reading over the thread and I missed what does the abbreviation DLI stand for. I did end up putting the photone app on the wife's phone and tried it out quickly, looks like I will have to try it again after upgrading it to full spectrum.

DLI is "daily lighting integral" which is the total accumulation of photosynthetic radiation over 24 hour period. For example, 550umol/s over 18 hours is comparable to 825umol/s over 12 hours...both offer the same accumulation of light but over a different ohotoperiod. Both are a DLI of 35.

basically is total accumulation of light over the day.

 

[VinDeezle]

If your wife has an iPhone, the app is acceptable as a guideline but can be hit or miss. Ive tried a few apps on android and they were incredibly out of whack with the light sensors on my phone. Photone has been the most reliable, but still way off.

For example, photone won't read over 630umol/s on either three of my android phones at all. Right now I'm at 880umol/s or 56k lux via the lux Meter, but photone won't go over 550umol/s. A few apps have calibration, but the issue I have ran into is the light sensors not being able recognise such stark light, not the actual conversion rate between the two numbers.

I actually get a more accurate reading on my phone's if I throw a piece of 60gsm paper over the sensor which blew my mind at first.

I've been reading over the thread and I missed what does the abbreviation DLI stand for. I did end up putting the photone app on the wife's phone and tried it out quickly, looks like I will have to try it again after upgrading it to full spectrum.

 

[Bullfrog]

If your wife has an iPhone, the app is acceptable as a guideline but can be hit or miss. Ive tried a few apps on android and they were incredibly out of whack with the light sensors on my phone. Photone has been the most reliable, but still way off.

For example, photone won't read over 630umol/s on either three of my android phones at all. Right now I'm at 880umol/s or 56k lux via the lux Meter, but photone won't go over 550umol/s. A few apps have calibration, but the issue I have ran into is the light sensors not being able recognise such stark light, not the actual conversion rate between the two numbers.

I actually get a more accurate reading on my phone's if I throw a piece of 60gsm paper over the sensor which blew my mind at first.

yeah photone on iphone with a diffuser is good. On android its completely and utterly rubbish

 

[Bear777]

If your wife has an iPhone, the app is acceptable as a guideline but can be hit or miss. Ive tried a few apps on android and they were incredibly out of whack with the light sensors on my phone. Photone has been the most reliable, but still way off.

For example, photone won't read over 630umol/s on either three of my android phones at all. Right now I'm at 880umol/s or 56k lux via the lux Meter, but photone won't go over 550umol/s. A few apps have calibration, but the issue I have ran into is the light sensors not being able recognise such stark light, not the actual conversion rate between the two numbers.

I actually get a more accurate reading on my phone's if I throw a piece of 60gsm paper over the sensor which blew my mind at first.

That's good to know, thanks mate

 

[veritas629]

If you try to absorb and use 100% of the info you're getting here on your first grow, you'll probably struggle a bit. Everyone on this forum, even the people with years of experience, are constantly learning and tweaking their set ups. You don't go from only eating mum's food to becoming a 3-star chef over night! HLG is solid and reputable light company, I've got a 550-R in my 4x4 tent right now. HLG's recommendations have been good for me and for many grows I just tweaked the dimmer or height until my plants looked green and happy. And remember, nobody growing weed at home had a PAR sensor before about 5yrs ago and most people still don't.

Remind yourself every so often: Even if you make a few mistakes growing your own, it'll still be better than whatever you're getting from a dealer!

 

[Pikey]

Well said @veritas629 it really shouldn't be (and isn't) as complex as some people choose to make it .

 

[Bullfrog]

not to mention the cost. $25 for 1 gram stick


Ive actually seen even worse its a shame job

 

[Bear777]

If you try to absorb and use 100% of the info you're getting here on your first grow, you'll probably struggle a bit. Everyone on this forum, even the people with years of experience, are constantly learning and tweaking their set ups. You don't go from only eating mum's food to becoming a 3-star chef over night! HLG is solid and reputable light company, I've got a 550-R in my 4x4 tent right now. HLG's recommendations have been good for me and for many grows I just tweaked the dimmer or height until my plants looked green and happy. And remember, nobody growing weed at home had a PAR sensor before about 5yrs ago and most people still don't.

Remind yourself every so often: Even if you make a few mistakes growing your own, it'll still be better than whatever you're getting from a dealer!

I understand completely what your saying. I really enjoy learning about it though and I will do my best to apply the basics first, while at the same time I like to know what options are available so while I learn I am aware of some of the practices others are using so I can keep them in mind and use what makes sense at the time, to help me get better.
Thank you for your reply, it helps keep me grounded

 

[veritas629]

I have a science and academic background, so I really dig into all the lights, nutes, etc. But, when I find myself tunnel visioning towards a $500 equipment purchase or $200 seeds, I remind myself that the white label Northern Lights I grew in a 40*40*120cm tent in a 35C closet and using generally bad advice was some of the finest herb I've ever grown!

 

[Indy]

Now that i've got a couple of grows done under a 1000w Full Spectrum LED. I found that having the light operate around 60-70% capacity, and at a height of 18" (45cm) above the canopy. I'm getting DLI readings of around 30 on the edges and 45 in the middle.

I'm getting a spot of foxtailing with it towards the end of grows. But i'm not sure if that's Light or Strain related yet.

EDIT: Grow setup. RDWC in a 1.5m x 1.5m tent, 2 x 45L tubs, with scrog screen.

 

[Kneeko]

Wow.. Too much for my stoned brain..
Ive just been using a Spider farmer SF 3000 (300w)
Never had a taco even with buds only inches away. on 100%

 

[Indy]

Wow.. Too much for my stoned brain..
Ive just been using a Spider farmer SF 3000 (300w)
Never had a taco even with buds only inches away. on 100%

That'd probably work considering its a 300w. From the info I've taken in over the last couple of years. It seems to me, a Full Spectrum LED light around 600w-750w range at a height of 18" or below would probably be a optimal grow light for the average personal grower. Well, those looking for a pound or better each grow.

 

[Kneeko]

I get about 10-12oz from my sqm of paradise with the 300w Led

 

[Madmick]

Now that i've got a couple of grows done under a 1000w Full Spectrum LED. I found that having the light operate around 60-70% capacity, and at a height of 18" (45cm) above the canopy. I'm getting DLI readings of around 30 on the edges and 45 in the middle.

I'm getting a spot of foxtailing with it towards the end of grows. But i'm not sure if that's Light or Strain related yet.

EDIT: Grow setup. RDWC in a 1.5m x 1.5m tent, 2 x 45L tubs, with scrog screen.

Could be too much blue and not enough red spectrum, might be worth checking what spectrum the light range is
The diablos are good is this department, no foxtailing
Seems a few ppl have this problem especially the cheaper nock up yourself models foxtails are common from 1 grow to the next

 

[Indy]

@Madmick this is the specs below, mate.

Specification: SE1000W LED Grow Light

LED: 3710pcs

PPE: 2.9umol/J

BTU: 3411Btu/h

Spectrum: 660nm,3200-4200K,4800-5000K

PPF Value: 2955umol@220V(1030W); 2943umol@277V(1000W)

Coverage: Core Coverage: 4FT*4FT (120x120cm) Max Coverage: 5FT*5FT (150x150cm)

Lumen：186738Lm±5%@AC220V；187150Lm±5%@AC277V

Power Draw:1000W±5%@AC200-277V

Light Size: 1151*1151*77MM

Gross Weight: 15KG

Noise Level: 0dB

Input Voltage: AC200-277V

Amp: 4.678A@AC220V; 3.608A@AC220V

Frequency: 50-60HZ

Link to light here.

What foxtailing is occurring is barely a problem. Just the odd one here 'n there.

 

[Madmick]

@Madmick this is the specs below, mate.



Link to light here.

What foxtailing is occurring is barely a problem. Just the odd one here 'n there.

Spiderfarmer , sorry mate , I think we've seen how good they are unfortunately

 

[Indy]

Spiderfarmer , sorry mate , I think we've seen how good they are unfortunately

Yeah, pretty shithouse light I guess..