What wattage for veg -

I recently purchased a Mars hydro TSW 2000. It states it will veg 4x4 tent or flower 3 x 3 tent. Can anyone help on adjusting the wattage, and what would be the best wattage for vegetation? Choices are 25, 50, 75, 100.

In my very limited experience, the only time you really need to dim a light is for very new seedlings and when you’re trying to encourage clones to root. Otherwise, crank that dial to eleven. (And if you don’t get that joke, I mean full power.)

Light to canopy spacing is important, so make sure you’re able to easily adjust that.

That light is “better” for vegetative growth than flowering. While it’ll work during all stages, the blue portion of the output is kinda wasted during flower. That’s to say you might want to keep an eye out for a second light that will better suit flowering. It doesn’t make a lot of sense to got from a 4x4 canopy down to a 3x3. Instead, you almost want two additional lights that’ll cover a combined 5x5 or 6x6 for flower.

I’m not saying your light is bad in any way. Just that you might consider adding more light during flowering.


I would say 50%-100% and double that for flowering . Really EZ to grow, I veg 2 plants with 2 95w light’s and flower with 390w on each plant

I’m currently running a single plant in a 2 X 4 tent using diy lights. The light is at 50% to allow some vertical growth and slightly increase node spacing. I won’t have these lights up over 200 watts until peak flower. There just isn’t any necessity to.


That’s a great point about manipulating internode length. I’m guessing you want more airflow, and avoid the stress of pruning might place on the plants.

I’m curious to know if the power consumption matches the light output, or if there are spectrum changes. In other contexts, optimal efficiency isn’t necessarily intuitive. Some machines are most efficient at 30% output while others work best at maximum output. Food for thought.


The higher end lights are extensively tested so there are numerous graphs and curves that can help you find the sweet spot. These LED’s are at peak efficacy around 75% of rated peak and I try to stay somewhere in that ballpark at peak flower.


When I was running my Viparspectra PAR600 I had all 3 switches on for the whole grow cycle from seed to chopping.


I wonder about lighting and efficiency claims? If you look at my fixture which is a Fluence Spydr X, it has a form factor of an array that more evenly distributes its output than a smaller form factor. The key to that is the par mapping. Many of the cheaper lights dont supply the relationship between the wattage that some of us are talking about and the dispersal of par. Let’s assume a fixtures form factor creates a hot spot in the center of the par map and that light has an output of 300 watts? Does this mean that the perimeter is getting significantly less share of that wattage? Or does it mean a similar 300 way array style light should more evenly spread the light and create a weaker hot spot? I think that’s where a high end fixture wins, the array may use the same power but be way more efficient in how it’s used and thus creates not only better coverage but also a brighter par map per watt.! You do pay for what you get!