PhytoMAX-3 General Information

Welcome to Your New PhytoMAX-3® SH Grow Light!

Please read and save this quick guide to your light.


  • Inspect the light for shipping damage, including any missing or broken LEDs. Do not plug in a light that has suffered shipping damage without consulting us first: or call us at +49 (0) 9131 9238691
  • NEVER look directly at the LEDs while they are on; eye damage may result.
  • We recommend wearing any UV-blocking eye wear such as sunglasses when viewing or working with plants under our lights. PhytoMAX-3 contains UV LEDs, which just like natural sunlight can irritate and damage your eyes.
  • Don’t over-load your electrical circuits – Two PhytoMAX®-3 16SH, 20SH or 24SH lights won’t fit on a standard 15-amp 110V household circuit! For more information and advice, consult your electrician!

Issues and Questions:

  • Black Dog LED wants you to be satisfied with your PhytoMAX-3 light!
  • Please note that our lights contain infrared and ultraviolet diodes that are outside of humans’ visual range, so it is normal for some of the LEDs to appear dim or unlit.
  • Our lights have a soft-start feature that takes up to 1 minute to achieve full brightness. This is a safety feature to protect your eyes in case you’re looking at the LEDs when they first turn on.
  • If you have any issues with your light’s function, please contact Black Dog LED, not the store it was purchased from. Call us at +49 (0) 9131 9238691 or see this URL:

Hanging Your Light:

  • We recommend tying a stopper knot at the loose end of the rope to prevent over-extension of each of the ratcheting rope hangers. See figure A.
  • Ensure that the structure you’ll be hanging the light from can support its weight plus some extra for cords, etc. – The PhytoMAX-3 16SH, 20SH and 24SH hanging points need to support almost 50 pounds!
  1. Insert a metal hanger clip into the hanging bracket on either side of the back of the light. Ensure that both ends of the clip are secure.
  2. Clip one end of each of the ratcheting rope hangers to the ceiling, and the other end to the metal hanger clips attached to the light. The ropes should be hanging straight, not pulling the hanging brackets toward or away from the center of the light. See figures B & C.
  3. Adjust the ratchet to hang the light at the recommended height as outlined in the table on the next page or from our calculator at
  4. Ensure there is always a minimum 6″/15cm of clearance on both sides of the light that have vents. Failure to provide adequate clearance can cause the light to overheat. The sides without vents and the top of the light do not require any clearance. See Figure D.

Recommended Footprint Sizes

(Square footprint, measurement given is one edge, use our calculator at for any custom situations):

* Average PPFD measurements are over the entire footprint, edge-to-edge and corner-to-corner, based on reflective surroundings or adjacent lights, and counting only PAR photons of 400-700nm. PBAR (280-800nm) photon flux will be 9% higher.
** When growing in an area smaller than the flower without CO2 footprint, CO2 supplementation is generally required to make full use of the additional light.
H.H. = Hanging Height above the average top of the plant canopy.

PhytoMAX-3 Growing Tips:

  • We recommend keeping your growing area 9-10 °F / 5 °C warmer than you would with other lights (85 °F / 29 °C normally) to maximize yield.
  • If you are going to burn sulfur in your growing area, remove the lights from the area, or turn lights off and seal in plastic during the sulfur treatment. Failure to do so will void the warranty on the lights.

Cleaning and Maintenance:

If your light requires cleaning:

  1. Spray water or a mild glass cleaner onto a soft lint-free towel (NOT onto the LEDs on the bottom of the light!)
  2. Gently blot the LEDs with the moist towel until clean. DO NOT RUB THE LEDs!
  3. Allow to air-dry, then plug your light back in and turn it on.
  4. NEVER spray any liquids directly on or around the LEDs


Made in Colorado, USA