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  • What is the difference between your Z2 and Z5 model and which should I use?

What is the difference between your Z2 and Z5 model and which should I use?

May 8, 2020 - 12:30 PM

  • The Z5 seems to be larger and I think it is what I need, but I am unsure.


  • Hello,

    In short, the Z2 and the Z5 are very similar in terms of build and internal parts. The biggest difference is that the Z5 draws more than twice as much power as the Z2 (112W vs 50W). This means it has an additional internal driver and more than twice as many diodes as the Z2. In practice, this results in the Z5 emitting twice as much light as the Z2 and also gives a bigger coverage area, which means it'll illuminate more plants.

    Below are the key differences between the LEDTonic Z2 and Z5 LED grow light.

    Z2 Measurements: L: 10 W: 8.2 H: 3(250*210*75mm)
    Z5 Measurements: L: 13.6
    W: 12H: 3 (347*306*75mm)

    Z2 draws 50 watts of power.
    Z5 draws 112 watts of power.

    Z2 has 90-degree focusing lenses.
    Z5 has 120-degree focusing lenses.

    Z2 has one power switch to activate all diodes.
    Z5 has two power switches, one that activates a blue-dominant spectrum and one that activates a red-dominant spectrum. When the Z5 has both the red and blue switches activated and both spectrum blends together, it has a similar spectrum to the Z2; a balanced spectrum that works very well from seed to harvest.

    Which lamp you should use depends on how large area you need to illuminate and with what intensity.

    The Z2 covers an area of 17x17/42x42cm with high intensity.
    This equals 2 sqft or 0.17 sqm
    The Z5 covers an area of 24x24
    /60x60cm with high intensity.
    This equals 4 sqft or 0.36 sqm

    Both lamps will work in larger spaces as well but the light coverage at the outer edges may be lower than ideal for high-light plants.

    Here is a light footprint comparison of the Z2 and Z5 inside a 3x3' reflective space. This information can be found on our website as well, but here is a direct link with the comparison uploaded in a larger version:

    I hope this information helped. Please let me know if anything was unclear or if you have any other questions.

  • Awesome! I appreciate the detailed reply.
    I have one more question.

    Why does the Z5 have two spectrums if both switches produce a balanced spectrum together? I've read that plants only use blue light during veg and red light during flowering. Is this true or not? Should I still use both buttons?


  • Plants will grow in a certain way depending on what spectrum they are receiving. This is called photomorphogenesis. When most plants receive a dominant red light, they will grow tall. When most plants receive a dominant blue light, they grow more compact and with a shorter distance between nodes (branches).
    This is simplified as some species don't react like this, wheat is one example, but we will generalize for simplicity. Most of the popular plants we grow indoors, respond like this.

    Some growers prefer to use a dominant blue light during the seedling and vegetative phase to keep plants more compact. Others prefer to have a red dominant spectrum, such as the light emitted from an HPS lamp, from seed to harvest.

    Plants will use all colors of light during all stages, but they will behave differently, depending on the spectrum.
    Our Z5 is designed to have a balanced spectrum that will work for all plants, from seed to harvest, with both buttons activated.

    I'd say most growers probably use both buttons at the same time, from seed to supply, but depending on your grow style and desired plant shape, you can experiment any way you want.
    The green switch on the lamp that activates the blue-dominant spectrum produces 40% of the Z5s total light output. The red switch that activates the red-dominant spectrum produces the other 60%.
    If you are using the green switch alone, the lamp must be a lot closer to the canopy to achieve adequate light intensity. This will result in a smaller light footprint and coverage area. So, in some cases, depending on how large area you need to illuminate, it will be better to have both switches activated and hang the lamp at a greater distance. This way, you can have the same center intensity, but a larger light footprint.

    One thing that is more important than spectral quality, is light intensity. If your plants are getting very little light, they will grow tall and lanky either way. Plants can grow more compact in a high-intensity but redder spectrum, than in a low-intensity but bluer spectrum.

    As the Z5 has two drivers inside it, we choose to divide the power into two switches and divide the spectrum into two parts, a blue-dominant and a red-dominant. This gives you the possibility to choose for yourself and experiment with different settings, based on the size of your grow space and desired shape of plants.
    We've made some small changes to the diode configuration on the Z5 and
    The spectrum produced by the blue switch alone is now similar to a white 6500k spectrum, in addition with two small red peaks.

    When the Z5 has both switches activated, it has a spectrum that is very similar to the Z2's.
    The Z2's diodes are powered with one driver only, which is why it doesn't have this feature.

    By the way, the red power-switch is not intended to be used alone. It can be used alone for an experiment or as a supplemental light, but this is not it's intended use or recommended for the average grower.

    Here is a link to the spectrum report for the Z5:

    I hope this answered your questions and cleared up any confusion.

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