Mars Hydro 300W Led Grow Light Review

When you decide to try your hand in indoor gardening, one of the most essential equipment you’re going to need is the grow light. But finding the best grow light in this market can be a tough ask, especially when you consider the sheer number of options available to you.

Mars Hydro is a manufacturer with a reputation for providing customers with quality grow lights. Today, we review the Mars Hydro 300 Watt LED grow light to see what features it has to offer. Is it really worth the money?

About the Manufacturer: Mars Hydro

Just like any other consumer, I’m sure you like to get know the manufacturer you’re about to do business with before you seal the deal. Partnering with an established brand somehow assures you that you are getting a quality product.

Well, when it comes to Mars Hydro, It is a highly reliable and trusted brand that has been serving us for almost a decade now. The company has multiple warehouses spread across countries like Canada, USA, Germany, Russia, the UK, as well as Australia.

Mars Hydro boasts a wide variety of full-spectrum LED grow lights, grow kits, grow tents, and related accessories. They are well conversant with the business and this is evidenced by the type of customer reviews they get on various online platforms.

The Review

If you are reading this review, it’s probably because you are either interested in or already started growing indoors. Providing your plants with the appropriate amount of light is essential for the perfect functioning of photosynthesis.

It is imperative that your light source delivers the right spectrum of light and in the right intensity. LED lights are beneficial because of their ability to provide a full spectrum. These lights are tuned to specific wavelengths and utilize less power than standard HPS lights.

If you are just getting started with indoor gardening, you may not necessarily want to make a large initial investment. Nevertheless, you also want to spend on something that will reduce your costs long-term, and this is, unfortunately, something that many newcomers tend to overlook.

While it is common knowledge that LEDs are considerably more expensive than their HID counterparts, they will also save you more money when you factor in long-term use. This is quite true because of the operational and maintenance costs involved.

The Mars Hydro 300 Watt LED light won’t stretch your budget with its price of under $100. It shields you from the costly initial investment and puts you in a position to enjoy all the benefits of LED light use.

It is a good choice for entry-level LED users who may not be willing to break the bank for their young venture. And just because it has a friendly price, don’t take it for a slouch. Read the following Mars Hydro 300W review to find out why.

Mars Hydro 300 Watt with Full Review

Mars Hydro 300 Watt Specifications

Dimensions: 296.3 by 262.3 by 79mm -This is a nice size for your startup indoor garden.

Weight: 2.4kg– is a manageable weight that you can comfortably hang over your indoor garden.

Coverage Area: 24” by 24”-This should give you decent overlap for your indoor plants.

LED angles: 90° and 120° angles– The Mars Hydro 300 Watt is a diverse product that features two distinct types of footprints. The 120°-angle is ideal for wide coverage and intense light in the area.

Lifespan: 50,000 hours– This is a long time that you can expect the LED light to continue diligently serving you.

Average Power Draw: 135W– This is considerably less compared to other LEDs in the market.

Noise Level: 56Db– The large fan on the Hydro 300W can get a little loud for some people.

Voltage Range: 85V-265V

Frequency: 56-60Hz

Spectrum: Full Spectrum

LEDs Wattage: 5W– These support plant growth by delivering uniform light.

LEDs number: 60

PAR Value: 445μmol from 18”- This is a functional value that facilitates impressive plant growth.

Read more: If you are looking for 600 Watt Grow lights please check our article or you can visit ViperSpectra 600W Review.

Watt Coverage and PPFD

Watt Coverage

One of the main aspects to focus on, as far as the Mars Hydro 300W is concerned, is the coverage area. The 24” by 24” max coverage is pretty decent for a grow light of its size and output.

The PPFD reading is another crucial factor because you may have a 2-foot area of coverage but if the light doesn’t penetrate the leaves of your vegetables, then it’s not very useful.

According to Mars Hydro, the 300W produces umols at 1.5 square ft from an 18-inch hanging distance. Directly under the LED grow light, the panel delivers 450 uMol from the 18-inch height, which is a good enough reading to support plant growth.

Each diode on the Mars Hydro 300W is covered by a tiny lens that channels the light on to the canopy. The combination of 90° and 120° angles offers great coverage, as well as penetration with wonderful intensity.

Power Efficiency

Growing led light power efficiency

This is a critical quality that many indoor gardeners tend to overlook when selecting an LED but later on come to great. I like the job that Mars Hydro has done on the latest version of their 300W LED grow light.

The old version would draw around 135W from your outlet but this new iteration pulls about 110 watts. For most grow lights, the power draw may fluctuate between 5 and 10%. And for the Mars Hydro 300 Watt, it is approximately 5%.

This is a very low power consumption mark that would be quite efficient if you are daisy-chaining several lights in your indoor garden.

Quality of Light

Quality of Mars Hydro 300W Grow light

The Mars 300W grow light features 60 ting 5W LED lights that together produce a light with a total of 300W. Additionally, it delivers a full spectrum light with a wavelength ranging from 430~440nm, 450~475nm 620~630nm, 650~660nm, which has been fine-tuned to suit plants such as flowers, vegetables, and Marijuana.

This grow light is also ideal for all growth stages given that it produces the proper wavelength for cannabis plants. The 5Watt LEDs are powerful enough to produce a light that can penetrate the deep canopy and are better than the 3-Watt chips you find in most LEDs.


All LED grow lights emit heat, but the Mars Hydro 300 Watt produces much less heat compared to most grow lights. This means that heat is not much of a concern. I actually expected there would be a drawback with the 5W LEDs, but the large fan does a great job of dissipating heat away.

The large fan at the back and the cooling slits on the sides of the LED are enough to keep the grow light cool. I’ve read through a number of reviews and I’m yet to find any user complaining about the heat on the Hydro 300W.

Safety Features

The cooling fan inside the LED panel functions whenever the grow light is on. It blows cool air on to the heat sink, helping to keep the diodes cool so as to function optimally. This does a good job of protecting the diodes from burning out.

Mars Hydro Safety Features
It Runs Really Cool, But That’s Expected from a 300W Grow Light

Another smart feature I noticed of the Hydro 300W is that diodes are not driven to their maximum capacity. When the LEDs are running over a comfortable and stable limit, this ensures that the components remain durable.

Furthermore, each diode on the LED has a protector that prevents reaction when one diode burns out. This ensures that the remaining diodes don’t suffer the same fate, ruling out the likelihood of a complete failure in the panel.

The Service at Mars Hydro

The Chinese are famous for producing affordable yet functional products for buyers who can’t afford the high-end prices. However, some users tend to avoid their products due to the bad reputation of some Chinese panels.

I wouldn’t say this is the case for the Mars Hydro 300W light. It actually seems to function quite well. I don’t remember experiencing any fading or inefficiencies when I was using mine.

I also looked through feedback from different indoor planters who use this light, and a large percentage had positive reviews. In addition to that, the company has two service centers in the USA, so you don’t have to worry about shipping your grow lights all the way from China.

You can communicate with the Mars Hydro customer service team by visiting their website. Their average response time is about 8 hours.


Mars Hydro provides its clients with a 3-year warranty when you purchase this grow light. You also get a 30-day money-back guarantee if your purchase turns out to be defective.


Mars Hydro 300W LED Grow Light Pros and Cons

What I liked

• It is readily available and very affordable light

• It is a highly energy-efficient LED light

• Uniform and optimal spectrum for all growth stages of green plants

• Long=lasting light with a low maintenance cost

• User-friendly setup

• Provides a full spectrum light for newbie marijuana growers

• UL safety standards for cables and wiring

• Long 3-year warranty and 30-day money-back guarantee

• Decent coverage area

• Adequate safety features

• Customer-friendly service team readily available on the net

What I Didn’t like

• Not water-resistant

• Suitable for small-sized indoor gardens

• It is meant for beginners, not professionals

• No dimmer included

Should You Buy the Mars Hydro 300 Watt LED Light?

Grow lights are very useful tools for those who are involved in indoor gardening or greenhouses. The Mars 300W is a great creation that provides you with a solution for this.

It is one of the most impressive small-budget grow lights you will find in the market, and will prove to be a great buy for any beginner looking to start indoor gardening on a small scale. If your budget is tight, you shouldn’t have a problem acquiring this nice LED light.

Final Thought

Generally, the Mars Hydro 300W LED grow light feels like a worthwhile investment for new entrants to the world of indoor gardening. It delivers a full spectrum light with low energy consumption and offers a high level of durability with little maintenance cost.

Most of the user reviews I’ve come across seem to be endorsing the product and after using it myself, there is very little reason to feel otherwise. This is despite the few drawbacks such as the smaller size and the unsuitability for professional indoor planters.

In a nutshell, this is a functional LED light that you regret owning. I would definitely recommend the Mars Hydro 300W to any beginner looking to invest in their first grow light. However, professional planters might want to keep on searching elsewhere.

Buy on Amazon

Last update on 2023-11-30 / Affiliate links / Images from Amazon Product Advertising API

Leave a Comment