VIPARSPECTRA XS1500, VIVOSUN VS1000, BESTVA Pro1000, SPIDER FARMER SF-1000, HLG Scorpion Diablo 630w,


To pick the best LED grow light in 2021 just search LM301B or LM301H, or check the description, it’s constantly updated

UPDATE: We have revised all of our recommendations based on actual use of the lights. We no longer simply do light tests because of the most neglected aspect with lights which is heat and actual grow performance. As stated in our top 10 mistakes video, I rather trust a light based on actual results before any light meter readings. All of the lights we recommend have been tested and their grows can be seen on our journals on discord.

Choosing a grow light can be daunting. LED lights are by far the best for growing weed and harvesting marijuana. Be ready! Narrowing brands down be confusing. Fortunately, the best technology that exists at the moment is the Samsung LM301B and LM301H diodes. These products are licensed by popular brands. ( Vivosun, Mars Hydro and spider farmer)

let’s dive into the illuminating world of light!

The main thing to look for is the quality of the diodes, the number of diodes and the distribution of the diodes. Some of the best lights will have high quality LED’s and the best ones have the patented Samsung LM301B or LM301H diodes. Factor all these in and look at the PPFD Map and the spectrum and you will have some guidance on how to narrow down your selections.

Disclaimer: We do NOT recommend products anymore that we haven’t actually used on a full grow run from start to finish. RESULTS of grow matter, so we have revised our approach in judging because we find that all PPFD maps are grossly exaggerated and the proof is in the pudding.

Spider Farmer SF2000:
Verified Grow:

Bloom Plus XP3000:
Verified Grow:

Companies to avoid: Viparspectra is terrible.

Photone Light Meter for Ios/android:

Our Picks: (clip coupon if available)

grow light amazon coupon
3 x 3 TENT

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4 x 2 TENT

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2 x 2 TENT

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4 x 4 TENT

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5 x 5 TENT

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Technology is amazing and every year it improves so drastically, it renders previous tech obsolete. LEDs or light emitting diodes are no exception. Never has there been a better time for lights in terms of affordability and efficiency. For decades, HPS or high pressure sodium lights was the industry standard. HPS had dominated growing indoors but in the recent years, LED’s rendered them obsolete.

let there be light!

Without getting into a drawn out explanation. Main reasons why the LED’s are dominant is because of the ability to control their light spectrum, less heat and they’re durability. The lights themselves are more expensive and make up for that ten fold! This is because of their their power consumption efficiency. (everything is better besides price)

Not all LED’s are made the same. The two main factors that you need to understand when choosing the LED is the spectrum/color range and light intensity. Light is an array of different colors and while blue lights deal with a plants leafy growth, red lights are better for flowers and buds. If you take a look at the suns spectrum, you will notice it includes a high level of light for all colors. Through science, we now understand that even sunlight has colors that are not fully utilized by plants. So, you’ll notice a drop in these wavelengths in efficient lights.

Light intensity is measured by PPFD. It is represented multiple ways. These maps show measurements at points on a grid. Each map is from a different distance. The two most common distances are 12 inches and 18 inches away.

Take note on the dimensions of then tent and measure up!

The optimal light intensity starts at 100 ppfd during the seedling phase.

As rows it gradually increases up to 1000 during flowering. You could go higher than a 1000, but to absorb the excess light. Plants would have to be supplemented with CO2. If not, the yield will actually diminish. I usually pick lights that have a ppfd reading of at least a 1000 in the center and 600 on the edge in any of their maps.


Today’s best LED lights are patented.

(companies such as OSRAM, SAMSUNG, CREE and PHILIPS)

Samsung dominates with their LM301B diodes. In 2019, Samsung released an updated version, the LM301H which is 5% more efficient and clocks in at 3.1 micromoles per joule. As of this videos release, it’s the most efficient diode commercially available. But, NASA uses a light that is 20% more efficient which is not available to the public.

Samsung LED is licensed. Only Some brands have the rights. So, the only difference in these grow lights are the number of LED’s and the placement of the diodes. You’ll notice that a brand such as spider farmer and bloom plus have LEDs spaced tighter around the edges. This gives a more evenly distributed light intensity. They are spaced out evenly. Therefore these lights have super high ppfd reading in the center. These lights also have drastically lower readings on the edge.  

Other optional features in LED grow lights is the driver which controls voltage and timer. A dimmer which controls light intensity and a timer useful to control what phases the plants are in.

To summarize this article, just search LM301B or LM301H. Look above for our top picks. It’s constantly updated as technology improves. Knockoffs and inferior diodes exist and may be cheaper off the bat, but the savings you will get from their efficiency will help you in the long run.


  1. I have a Mars Hydro TSW 2000. My tent is a 2 1/2 ×2 1/2. Is that sufficient for this tent as far as light spectrum and ppfd in veg and Bloom, even on the edges?

    1. 2.5 x 2.5 = 5.25 X 30 = ~158 watts needed so yes that’s good enough

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