Hi all I have a spider farm se5000 and am going to...

got to agree with @NobodysBuds good grower right there, very technical.

Thanks guys So much info. And still so many questions And that’s sweet. Guess first I need not to over water and learn the simples Learn to watch the plants Then add maths and and clever stuff.

par apps are often inaccurate, fyi. They are probably proportional, at the least... so when you find a peak # at a specific distance, that's your "100%" and 50% of that will be 50% of par. "max" dli depends on several relativistic factors, so your "max" is likely different than anyone else's for a plethora of causes. It will get you close, but you'll have to observe and react. Most plants will want teh same thing, even so you may find some that need more or less... but having a solid starting point makes that whole process much faster and more precise - act with confidence. So, use any info you find as a ballpark idea. Figer 35-40DLI in an uncontrolled environment, and pushing low 50's DLI in a tightly controlled environment. The latter requires additional CO2 and some control over our temps and RH% to match needs of current stage of life cycle. (VPD chart is a good ballpark guide) Use internode length to assess your choices... too tight and it needs less, too stretchy and it needs more. Take measurements when you find that happy zone. start there in future. If you change apps... compare 2 measurements and see if they are equal or not... most the time it's really just a "Lux meter" and a stock conversion factor... since most lights have a very similar curve in that regard, it can be fairly accurate -- maybe +/-10% off? If you ever use that app under a different light, expect some slight differences in what the values translate too -- again, because it's actually a lux meter in sheep's clothing. A 3000k base white diode light may not read the same as a 3500k base diode light, all other things remaining the same including umol/s of PAR radiation. The picture you have attached is for ambient CO2 and nothing too crazy environmentally, but not tightly controlled, either. Figure 20-25% more on the peak values.. probably similar on early vege etc, since that is a different dynamic than a robust, mature plant begging for light. I'd gues more likely 800-900ppfd for ambient co2 in a typical house.. it's much higher than "300ppm" you often see quoted as 'ambient'. 1200-1300ppm is rough ceiling for adding CO2. if you do that, you need to also control environment or you are wasting some portion of effort to add that co2. you know you are over DLI relative to environment and stage of life by the behaviour of teh plant.. it's not the most precise way, but you can see if it stalls, wilts or is droopy for long periods when lights are on. Spots forming near top would be a sign of severe light damage. I took a look at the SE5000 specifications... if the diode count and such is accurate, the math is at least close to what they advertise -- that is unusual... the norm is bat-shit crazy claims, so this is a good thing. This means you can use that ~1300 umol/s with some confidence to calculate your DLI relative to hours of use and area of coverage and expect it to be fairly accurate. Good job spider farmer for not lying through your f'n teeth on the SE5000 like 80%-90% of all light manufacturers, lol. it's a good didoe count (~.29w/diode is near diminishing returns - excellent) with a low to mid-bin quality diode (just a few percent less efficient being main difference), but probably not the "SJ" bin for the warmer CCTs used, which hopefully are the bulk. my problem with a lot of these manufactures is they have a too-cool CCT for something tehy sell as a seed-to-harvest light. Plants vege just fine under a 2700-3000k light and the benefits in bloom phase far outweigh that minimal impact in vege. go check out the lm301 spec sheet at samsung.com. know that 'other' diodes are less efficient but usually 5% or less of total diode count too... so expect a little lower than what the lm301 shows in the various tables for bin and CCT options. you'll notice teh "5000k" or whatver is the peak and what you sometimes see falsely advertised or used to calculate a false "efficacy". No worries on the "1300umol/s" claim by spider farmer... looks legit. Even though you don't need it, a slight breeze over them will make them last the advertised 50-60k hours before they dim to 90% of original intensity... (white diodes only for certain.. spec sheets will inform about others used from original manufacturer of diode. those spec sheets are accurate.)

Hey man. I already know what it should be, but I'll send u a chart. With most stuff you'll find for your range in light that 40% for seedlings and 100% for growth/flower but I like to do 80% for growth and keep the 100% for that eextra boost once stigma, (pre-flowering) has started. Heres a similar light to yours and it stats what are the best for growing. 30cm away keeps the PPFD in the range it's advertised to be at. https://www.led-grower.eu/viparspectra-pro-series-p4000/ Happy growing good luck pal.

Search online for "DLI chart" which is Daily Light Integral. A plant needs X amount of photons/light per day. You can give it more light for a shorter period or less light for a longer period. This chart tells you how much light for how many hours. Here is a website with the chart and more explanation. https://www.ledtonic.com/blogs/guides/dli-daily-light-integral-chart-understand-your-plants-ppfd-photoperiod-requirements