How do I stop stretching?

The stretching is based on light intensity. Just increase the light strength. If your tent is only 3 feet tall you will have other issue coming very soon. I struggle in a 5 foot tall tent at times.

If the plant falls over without stretching, it's too much light. If nodes stack to tightly, it's too much light. Observe and adjust. You recognize the stretching already for too little light. will go over at least 2 paths you can take... One route you can figure out likely watts per sq foot you need, but this will heavily depend on efficacy of your lights Also, assuing it's a lm301-based LED. This will be faster and only showing above average to high end efficacy range, since you diy'd it i doubt it'sa low diode count. Watts per diode and diode bin will dictate efficacy. (Samsung lm301b/h only -- 0.25w/diode up to 0.40-.50w/diode is the range i'm trying to cover below) i see it's diy, but is it kit that is marketed as a "1000w equivalent" or actual 1000w? Use actual watts when trying to deduce dimming % from this. Assumes 18.6 vege and 12/12 bloom. You want 20-25W/sq ft max for vege at 18"-24". And, 30-37.5w/sq ft in bloom at same distance, which you can see is 150 % more watts. Any change in distance from canopy impacts evenness of light coverage. i prefer to let that geometry dictate exact distance from canopy. Inverse square law applies to distance from canopy, so it doesn't take much to impact DLI. Let's say it's a 4x4 or 16 sq ft and a high efficacy ... so 16sq ft*20w = 320w.. or roughly 50 % power at 18-24" for mature vege phase --- less for seedlings and ramp up as needed to this 50 % -- with dimmer, distance or time per day within reason. Math, thinking and applying.. oh, this is much longer, lol... but if you understand the why and the how, it makes applying these concepts in other ways too. 50-60 % and 30-36" from seedling to start? Whether the diode or the driver, there's no guarantee you retain same spectrum flux emitted the further you dim below spec sheets testing. Do it if you must, but i try to avoid going below 50 %. You'll need to add more as teh plant matures. Most likely around 66 % if light is well-fitted for space and allowing best distance from canopy for distribution of light to dictate height from canopy, which will be 18-24" in most cases. We'll use a more apples to apples term for measuring amount of light provided per day to a plant that will be explained later -- DLI, daily light integral. DLI applies regardless of garden size or hours a day of light (vege, bloom, autos, doesn't matter to DLI) When you go over 40ish DLI you start seeing damage from light under normal circumstances (maybe, 55DLI with augmented CO2 and tightly controlled VPD). 40 DLI is a good estimate for maximum amount you can give per day given only atmospheric CO2 and relatively safe temperature and RH % . While, 21-22 DLI is about as low as you can go expecting a decently formed bud. So, even at maturity, you may only be using 66 % power 18hours/day at 18-24" from canopy -- 150 % of that is 100 % power at 18-24" away in bloom phase because you have 2/3rds the hours of light per day. The more well-distributed the light is, the closer you can get with less dramatic hotspots. Required coverage tends to dictate how high you need it more often than not. Height from canopy quickly impacts canopy DLI and needs to be considered. My 650w isn't a continuous dim knob. It is running at "80 %", 16hrs/day (1/9th less hours than 18 - equivalent of 71 % dimming 18hrs/day) and 2-4" further from canopy than "normal" to get down to 35-40DLI range. When i flip to bloom i need a proportional amount more light relative to change in hours, in this case 1.33x (if 18/6 you need 1.50 %) to get around 35-40DLI. I know in hindsight that these were a great starting point and allowed plant to dictate any adjustments. Unfortunately i brain farted, treated as if it was ona 12/12 schedule and stunted hell out of my plants first use, LOL, but it's very close to what typically works best through experience. Had i not been a dumb ass, my first run would have been much smoother with these lights. Calculate PPFD/DLI example for this light -- 100 % power and covering 4x5 space give or take. 1900umol/s/20sq ft = 95umol/(s*sq ft) 10.764ft^2 per m^2 * 95umol/s per ft^2 = 1022PPFD, which on a 16/8 cycle is 58.9 DLI -- (reference DLI table - google image search "Daily Light Integral table") Holy shit, batman, that's gonna kill a plant! On a 11/13 cylce it is 40.5 DLI, which might need an extra inch or 2 from canopy than normal as I do in vege(not a coincidence). Anyway 40dli/58.9dli = 67.9 % -- So, not surprisingly we need about 66 % of that over 18/6... 3/2 -- 2/3 recipricols should make sense.. (aka 150 % vs 66 % and 18hours for vege phase vs 12hours for bloom phase) Given the rounding and guesstimates, 67.9 % is damn close to 66 % and why i need those extra inches from canopy as it is likely on high side given the math too. Your dimmer knob eliminates need to screw with distance from canopy.. let geometry and best blanket of light dictate that. A free lux meter app can help with choosing best distance from canopy, as it is proportional to umol/s & ppf but is definitely not the same thing. if central area klux reading is considered "100 %" and outer area is 50 % of that central klux reading, the umol/s or ppf would be 1/2 of the central umol/s reading with 500 $ quantum meter. With lux meter you can maximize your edges/corners and know if sacrificing too much in middle, reverse course... best overall average is a good goal. measuere several locales at same distance from lights. it's all proportional. your better dimmer knob will avoid the adjustments i have to make to light cycle time and canopy distance (not related to preferred optimal coverage). If the light is a perfect fit for size of garden, it'll be near 66%. If you need more than this and not related to distance, the light might be a bit underpowered in 12/12 bloom compared to 18/6 vege. You could reduce distance from canopy, but this also reduces optimal light footprint, which is fine if there's room to spare or buds on edges will sufer more than normal. You can also implement a 13/11 cycle safely, which will give you 8% (or 1/12th) more DLI than 12/12. If less than 66% it's a little over-powered for the area of coverage and you probably want a slight <100% power in bloom or a bit futher away from canopy. (I'd sugget the latter here... more photons spread out is better than fewer that are focused unless difference in watts is huge you'd actually save more than a pittance per month.) So, when you find that sweet zone for roughly 66 % power (or whatever) on 18/6 cycle, it's easy to know what you'll need when you flip to 12/12 (150 % if going from 18/6). Early vege + ramp up the next time will go smoother too, especially with afew notes this time. Observe and react to plant is all we can do without a 500 $ quantum meter and that only gives a more consistent/precise measurement that can reduce how much we must observe and adjust before finding a relative optimal. Some variation is expected per plant genetics and unless you tightly control your environment, that too. If you have honest specs, can use the umol/s and area you cover with light to calculat PPFD and reference a DLI chart. While other factors are relevant, this is best way to understand light photon by photon in the PAR range. size of garden and light schedule doesn't impact comparing your garden to another with respect to light provided... Look up the utah state dr bruce bugby videos on youtube... "maximizing yields...." is a good one and there's a few others more dedicated to lighting... great info on light and nutrients in his videos.