Medic Grow Smart 8 Plus Review

The Medic Grow Smart 8 Plus is an upgraded version of the very popular Smart 8. It features the industry leading Samsung LM301h diodes. I tested the original Smart 8 last year and was impressed. Like all Medic Grow fixtures, the original Smart 8 performed very well and is an incredible value. The new Smart 8 Plus is somewhat more expensive, and I was curious if the performance improved enough to justify that added cost.

The Medic Grow Smart 8 Plus features the leading Samsung LM301h diodes whereas the original Smart 8 uses Sanan diodes. However, the diode count is the same on both models. The Smart 8 Plus features 2880 full spectrum Samsung LM310h diodes with a 4000k color temperature. There are also 80 Osram 660nm red diodes. In total there are 2960 diodes with a published power draw of 760 watts. That is 3.9 diodes per watt or 0.26 watts per diode on average. However, the 80 Osram diodes are higher rated and use more power per diode.

Like the original, the Smart 8 Plus is a sleek foldable LED grow light with 8 LED bars. It has a nice white finish and looks stylish. The drivers are housed in a central chassis along with control knobs and a digital display. The built-in digital display shows the power setting, an estimate of the PPF, and other key information.

One of the unique features of the Smart 8 is the built-in timer. You can set the light cycle by simply selecting a setting with the timer knob. For example, if placed on the 12h setting, the timer will initiate a 12 hour on sequence followed by 12 hours off and then repeat. When I tested the original Smart 8, I found a few issues with the timer functionality. To their credit, Medic Grow took my feedback and upgraded the timer function and added memory on both versions of the Smart 8.

The timer works well and eliminates the need for a separate plug-in timer to control the lights. If you use the built-in timer, it will activate a sunrise and sunset sequence. The sunrise sequence is helpful to ease plants into the full density light.

In addition to the timer knob and the dimmer knob, there is also a bloom button. When the bloom button is not activated, the display will read V1 Spectrum and the 660nm diodes are reduced to 60% power. When the bloom button is activated, the display will switch to F1 Spectrum and the 660nm diodes are driven at 100% power. The idea is that growers may want to reduce the amount of red light during the vegetative stage to reduce unwanted stretch. If the plants are growing lankier than you’d like, you can switch the bloom button off, otherwise I would leave it on. I tested it both ways.

I ran the Medic Grow Smart 8 Plus through the same 9 tests that I ran with the original Smart 8. Overall, the Plus does slightly better than the original, but it is actually very close.

First, I ran PAR and ePAR tests in a 5×5 area with the bloom button on and off. For these tests, I set the hanging height so that the maximum PPFD is exactly 1000 µmol/m². With the original Smart 8, that height was 58cm (23in) above the sensor. The new Smart 8 Plus is a little more powerful and it requires a higher hanging height, 64.5cm (25.5in).

Compared to the original Smart 8 tests, the Smart 8 Plus delivered a higher Usable PPF (1807µmol vs 1744.4µmol in the ePAR test with Bloom on). However, the Photon efficacy is almost exactly the same in all of the tests. The increase in usable PPF is largely a result of a higher power draw. However, coupled with the higher hanging height, the increase in Usable PPF does make an improvement to the map. In the corners the density is almost 50 points higher with the Smart 8 Plus.

When I switched the Bloom button off, the power draw went down by about 7.5%, but the PAR and ePAR values only went down by about 6%. Like the original, the Smart 8 Plus is slightly more efficient with the Bloom button off. With the Bloom button off, the PAR photon efficacy goes to 2.26 µmol/w (from 2.23 µmol/w) and the ePAR photon efficacy goes to 2.37 µmol/w (from 2.33 µmol/w). This is interesting, but not significant enough to dictate the best option. In most grows, I would leave the bloom button on full time.

The Smart 8 Plus performs very well in a 5×5 grow space. However, I know that a lot of growers are using them in 4×4 spaces. While it will physically fit, it is really a lot of light for a 4×4. To be effective, you will need to elevate the level of carbon dioxide in a sealed space or dim the Smart 8 Plus to 80% or 60%. I ran the full powered tests for growers in sealed spaces with elevated levels of carbon dioxide first.

When plants are grown in ventilated spaces, the ambient level of carbon dioxide (about 400 PPM) limits the amount of light that they can safely process. I recommend a maximum light density in the PAR range of 1000 µmol/m² for growers with ambient levels of carbon dioxide. However, plants in sealed rooms with elevated levels of carbon dioxide can safely process more light. Plants can process up to a maximum of about 1500 µmol/m² if the carbon dioxide is 1200-1500ppm.

With the original Smart 8, I lowered it to 30.5cm (12in) and got very close to 1500 µmol/m² (1481 µmol/m²). With the new Smart 8 Plus, I was over 1500 µmol/m² at 30.5cm. I raised the Smart 8 plus up to 35cm (14in) and hit the 1500 µmol/m² target exactly. Compared to the Original Smart 8, the Smart 8 Plus has slightly higher Usable PPF and a better distribution due to the higher hanging height.

Full power in a 4×4 tent will produce great results for growers who can keep the carbon dioxide PPM at about 1200. For most growers, including all growers who control climate with an exhaust fan, having good results in a 4×4 will require dimming. The Smart 8 and Smart 8 Plus can be run at 80% if you have enough hanging height, but they can also cover a 4×4 at only 60% on the dimmer. As with the previous tests, the Smart 8 Plus is slightly more powerful than the original.

At 80% on the dimmer knobs, the performance of the Smart 8 Plus is very similar to the performance of the original Smart 8. I measured the maximum PPFD of 1000 µmol/m² at the same height with both fixtures, 66cm or 26in. The Usable PPF and the maps are almost the same. However, the Smart 8 Plus is throttled more by the dimmer than the original Smart 8. At 100% power, the Smart 8 plus pulled 26 watts more than the original Smart 8. However, in the 80% tests, the Smart 8 Plus pulled 17 fewer watts than the original. In both sets of tests, the 80% PAR and ePAR maps in the 4×4 space are incredible. The Smart 8 plus, with a lower power draw, has a higher photon efficacy.

At 60% on the dimmer, the Smart 8 Plus pulls 455 watts and the original Smart 8 pulled 458 watts. The similarity of power actually makes this test the easiest comparison between the two fixtures. The Smart 8 Plus has a higher photon efficacy and put out more light. I only ran ePAR tests at this height. With the Original Smart 8, the Maximum ePAR at 30.5cm or 12in was 989 µmol/m², which is close but below the limit. The new Smart 8 plus hit the limit with a maximum of 1037 µmol/m². The lowest ePPFD improves from 566 µmol/m² with the original Smart 8 to 599 µmol/m² with the Smart 8 Plus.

The 60% test is really impressive. After testing the original Smart 8, I was impressed enough with the 60% test that I ran the Smart 8 in my grow for one cycle. It was a great harvest and easy grow to manage with less than 460-watts. It needs to be noted that the new Smart 8 plus pulled 2.64 µmol/w in the 60% test. This is truly exceptional performance. I loved the original for this test, and the Smart 8 Plus is better.

I tested the dimmer on the Smart 8 Plus in the 5×5 area and found it to be accurate throughout the dimming range. The on-board dimming knob has preset positions at 40%, 60%, 80%, and 100%. You also have the option of connecting it to an external controller for finer granular control of the dimming. As you dim the Smart 8, the estimated power usage and PPF on the digital display will go down. As you can see in the test data, there is a steady relationship between power, PPFD and ePPFD percentage. The density of light is a few percentage points higher than the power.

After I ran the 4×4 CO2 Par and ePAR tests, I measured the operating surface temperatures. The room is climate controlled at 25.5C (78F). The fixture had been running for over 2 hours continuously when I measured temperatures. The casing on the central driver only hit a temperature of 41.8C (107.2F). The LED bars hit a high temperature of 49.3C (120.7F). At full power, the Medic Grow Smart 8 Plus will add 2,650 BTU/hr to a grow space. Only about 7% of that (185 BTU/hr) is from the drivers in the central chassis.

I have always been impressed with the value of the Medic Grow fixtures. They are solid great performing lights that are usually incredible deals. Three Medic Grow fixtures that I have tested set all time records for cost efficiency. I am somewhat torn because this new Smart 8 Plus goes in a different direction.

The Samsung LM301H diodes are extremely popular. They are great diodes and growers are clamoring for them. Manufacturers like Medic Grow want to give growers what they are asking for, but there is a cost. The LM301h diodes come at a premium cost. Manufacturers either skimp on the quantity or they have to pass along the costs. I commend Medic Grow for not lowering the diode count, but they did have to raise the price.

You get the best deals on Medic Grow lights through their website with discount code CCFC. They offer fast free shipping and code CCFC saves you 10% off regular or sale prices. With the discount, the Original Smart 8 will cost about $566 ($0.32/µmol) and the new Smart 8 Plus will cost about $701 ($0.39/µmol). Some growers may decide that the improved performance is worth the added cost for the Smart 8 Plus, but the original Smart 8 remains an excellent light and the lower price point makes it very attractive.