Led lamp

I'd go at least 150w with a mid to entry level LED. (you'd run at 100-120w during vege, then 150w during 12/12 cycle -- if no dimmer, distance from canopy is equally effective and in some ways better - probably immerses lower parts of plants better with more photons coming from the side due to longer angles of reflection.) If you only grow autoflowers, could probably do 100-120w on an 18hour cycle.. The more efficient the light is, the fewer watts needed to produce same number of photons. If you can find a roughly 300+ umol/s light with fewer watts, that too will work well. Be wary of advertised efficacy (umol/J) and intensity (umol/s). A higher end light should be running at about 0.25-0.30 watts per diode, if it is claming a 2.7-3.0 umol/J efficacy. The suggegstion above for a entry-mid level is closer to 2.3-2.5umol/J range.. .this is directly proportional to electric bill. So it's 25-33% more expensive per month for an entry level vs higher end light. No big deal at 150w, but if you go bigger in future, save up for the more efficient LED lights. w/s = j/s so umol/s * w/s = umol/J when simplified. you can think of it as umol of light per watt per second, if that makes more sense. (umol = micromole, a somewhat arbitrary way to count number of photons or molecules.) A "mole" is the number of hydrogen+ ions that adds up to 1 gram. 'micro' is 1/10^6 of that .. it's a huge number still. 6.022*10^23.. micromole is 6.022*10^17 photons, in this case) This is how we can calculate interation between photons and molecules on a 1:1 basis. densities vary, so mass alone is not sufficient to do this in any useful way. long story short... learn umol/s ... don't use watts. learn how to use parts used to red flag bullshit specifications. samsung's spec sheet is accurate. light spec sheets often take that information out of context. the watts/diode is the easiest way to see if they are lying.