Atreum Hydra 3200 Review

The Atreum Hydra 3200 is an innovative LED bar Grow Light designed for 4’ x 2’ coverage. It has more than enough power to fill in a 4’ x 2’ space. There are 4 bars that run the long way and the diodes are algorithmically distributed towards the ends of the bars. The design leads to exceptional uniformity with PAR and ePAR maps that I grade as A+. If you are looking to maximize production in a 4’ x 2’ grow tent, the Atreum Hydra 3200 may be the best light.

Atreum Lighting is a USA company based in Seattle Washington. I previously tested the smaller Atreum Hydra 1000 (Test Report). Atreum is an innovative company. They were among the first to bring fixtures with algorithmically spaced diodes to the market. The Hydra 3200 takes advantage of this innovation and creates an exceptionally uniform distribution of light across the 4’ x 2’ canopy.

The list price for the Atreum Hydra 3200 is $419. We have a 10% discount code for all products on Atreumlighting.com. Use discount code CCFC. That will bring your cost for the Hydra 3200 down to about $377.

I discussed the Hydra 3200 with Mike Lin, the founder of Atreum Lighting. He explained that they wanted to make a light that gives growers more power and flexibility. He also put an emphasis on even distribution of light and the algorithmic placement of the diodes. Together, these features allow the Hydra 3200 to fit a ton of light into a 4×2 space without exceeding the density limits for growers without supplemental carbon dioxide. Mike explained that the dimmer allows both precision and granularity, so different growers will be able to dial in the exact density they desire.

The Atreum Hydra 3200 features full spectrum diodes from LEDestar. LEDestar diodes perform slightly better than the top Samsung diodes in independent testing. Mike explained that they did their own tests to confirm that. They made separate LEDestar and Samsung versions of the Hydra 3200 for testing. The LEDestar version performed better and cost less. I have previously tested the Mogobe Octopus which also uses LEDestar diodes. I was introduced to Tony Chen from LEDestar and plan to collaborate with him on an upcoming video project about the science of LED diodes.

The Atreum Hydra 3200 has a total of 1,136 diodes, which is about 3.55 diodes per watt. There are 768 full spectrum LEDestar diodes at 3500K and 320 full spectrum LEDestar diodes at 6500K. There are also 48 660nm deep red diodes from TD. The diodes are powered by a Sosen driver with a digital dimming display. The driver and dimmer can be mounted on the fixture or easily removed.

I set up the Atreum Hydra 3200 in the 4’ x 2’ test area at full power and measured a maximum PPFD of 1000 µmol/m² at a hanging height of 49cm (19.5in) above the sensor. I ran a complete PAR test with the Apogee SQ500 PAR sensor and then an ePAR test with the Apogee SQ610 ePAR sensor. ePAR includes all of the PAR light plus far-red light up to 750nm.

The distribution of light across the 4’ x 2’ canopy is exceptionally good. In the PAR map, the maximum PPFD is 1000 µmol/m² and the lowest PPFD is 802 µmol/m². The Atreum Hydra-3200 is the first fixture that I have tested to keep the corner PPFD values above 800 µmol/m² in its intended coverage area. In the ePAR range the values all go up by about 40 points. Notably, the ePAR map has values above 1000 µmol/m² from the top edge to the bottom edge.

The average PPFD across the PAR map is 913.1 µmol/m². That converts to a usable PPF of 657.5 µmol. I measured a power draw of 316 watts, which gives the Hydra 3200 a Usable Photon Efficiency of 2.08 µmol/w in the PAR range. The average ePPFD in the ePAR map is 951.8 µmol/m². That converts to a usable PPF of 685.3 µmol. The Usable Photon Efficiency in the ePAR range comes to 2.17 µmol/w.

The maps are truly impressive. I think Mike followed through and the Hydra 3200 is giving growers even more light than they need in a 4’ x 2’ space. With corner PPFD values above 800 µmol/m². I wondered how much I could dim the Hydra 3200 before the lowest PPFD values dropped below the 500 µmol/m² threshold for optimal efficiency.

The digital dimmer allows granularity and precision. I put the PAR sensor in the corner with the lowest density reading and ticked the dimmer knob all the way down to 58% before it dropped below the 500 µmol/m² threshold. I ran complete PAR and ePAR tests with the dimmer set to 59%.

In the 59% PAR and ePAR maps, the phenomenal distribution from the Hydra 3200 is on display. The maximum PPFD in the PAR map is 632 µmol/m² and the lowest PPFD is 506 µmol/m². In the ePAR map, the maximum ePPFD is 657 µmol/m² and the lowest ePPFD is 536 µmol/m². The fact that the Hydra 3200 can keep the entire canopy in the prime photosynthetic density range at only 59% power speaks to both how powerful the fixture is and how well it distributes the light.

The dimmer is a selling point for the Hydra 3200. The dimmer is key, because full power may be a bit much for many growers in a 4’ x 2’ tent. It is a continuously adjustable dimmer with a digital display. This gives flexibility to set the dimmer at any power setting and confidence that the setting is correct. In my test, the PPFD and ePPFD values ran just slightly higher than the dimmer setting throughout the dimming range.

The amount of heat that a light adds to a grow space is a function of the power draw. The design goal for any fixture is to dissipate that heat so that the fixture itself does not get too hot. Running hot will lower the efficiency and shorten the lifespan of a fixture. The Atreum Hydra 3200 dissipates its heat well and runs rather cool. The maximum temperature that I measured on the LED bars was only 48.4C (119.1F). The Sosen driver ran a few degrees warmer at 51.7C (125.1F).

The Atreum Hydra 3200 is an innovative fixture that will smother a 4’ x 2’ tent in high density light. I think the dimmer will rescue many growers, because you need to have your grow dialed in or the plants will suffer under so much light. However, there is no shame in having more power than you need. The Atreum Hydra 3200 produces the best PAR map I have seen in a 4’ x 2’ space, and it has the highest harvest potential!