Lumatek Zeus 600w Pro 2.9 & 2.7 comparison

by Craig P

Lumatek Zeus 600w Pro 2.9 & 2.7 Comparison

Lumatek Zeus PRO 2.7 -

Lumatek Zeus PRO 2.9 -


New to Market

With the arrival of the New Lumatek Zeus 600w Pro 2.9, many growers will be curious to know how it stands out from its 2.7μmol/s/J cousin; whether it’s worth paying that little bit more for the extra performance it offers or - for those who already own the Zeus 600w Pro 2.7 - if it’s worthwhile upgrading.

We’ve done some testing of our own to help you answer these questions yourself.

What are the main differences between the two?

In short: the bars. While the design and main features of the Zeus 600w fixtures have stayed the same for the 2.9, Lumatek have focused their development efforts on improving the output efficiency of each bar.

This has mainly been achieved in two ways:

Firstly, the ‘hard lens’ cover seen on the previous model has now been replaced with what Lumatek refer to as ‘clear glue protection cover technology’. This is essentially a silicone coating (commonly called a ‘conformal coating’) and something that is widely implemented across the UK LED grow light market as both a way of ensuring electrical safety compliance and as a more effective way of transmitting light (with less photon-to-heat losses) than a hard plastic lens.

Secondly, Lumatek have increased the electrical efficacy of the PCB by both improving the quality (bin) and the recipe of the diodes being used. This has been achieved by using higher efficiency diodes and proportionally more red within the mix. With red diodes possessing both a higher electrical and photon flux efficacy than white ‘full spectrum’ diodes, Lumatek have been able to increase overall efficiency to 2.9μmol/s/J while staying within an appropriate wavelength range to ensure effective photosynthesis and wholesome growth.

PAR maps

As well as providing you with a PAR map so that visual comparisons can be made between the two Lumatek Zeus 600 Pro versions, we think it’s useful to quantify these differences as best as possible and compare our results with the official specifications. Bear in mind that while our Apogee quantum meters are incredibly accurate and the perfect tool for assessing real-time usable light distribution, their limitations should be included within the range of variables that could affect the difference in the numbers we see (including input voltage, power consumption, ambient temperatures, human positioning error etc). With that being said, the deviations are small enough (5-10%) to provide a more than acceptable reference for comparison.

Both of the PAR maps for these lights were taken in identical, mylar reflective 1.2m grow tents, at full power and hung at 18 inches from a black grid.


Zeus 600w Pro 2.7 (610 watts at the wall)


Zeus 600w Pro 2.9 (620 watts at the wall)

Crunching the numbers

First of all, let’s look at the difference when we total all PPFD numbers taken from each PAR map:

Zeus 600w Pro 2.7 - 53644
Zeus 600w Pro 2.9 - 59373

Difference between - 10%

Now let’s compare the difference in PPF (that’s total light output) between the two, as stated by Lumatek:

Zeus 600w Pro 2.7 - 1770
Zeus 600w Pro 2.9 - 1620

Difference between - 9%


Based on our testing, these numbers leave little doubt to us that this light does in fact produce about 10% more light than the Zeus 600w 2.7 and is in line with the numbers that Lumatek are providing. It's worth mentioning here that from our own experience, Lumatek are in the minority when being honest about their performance figures.


So it is worth the extra money?

If you’re in the market for a large, ultra-efficient, genuine 2.9 micromole-per-joule light with a price tag that doesn’t make the eyes water, then you simply won’t find a better value fixture than this. Whether you need this level of efficiency over a higher wattage LED with an equivalent total light output will depend on your own circumstances, such as: current ambient temperatures, air-exchange capacity, kWh cost - and whether you’re looking at this from a ROI perspective. Based on current average domestic electricity costs, a saving of 10 watts over 5 years is negligible (about £50-£80). The ability to increase overall yield from increased photosynthetic rates really comes down to the individual grower and their ability to maximise the extra usable light that the Zeus 600w Pro 2.9 will provide; it’s not something we’re able to simply quantify.

For 2.7 owners who were initially appealed by the high efficiency of the 2.7 and feel as if they’re already maximising its use, then the extra photons will certainly come in useful. From a pure value-for-money perspective, it’s worth looking at the price vs PPF difference in these fixtures to make an assessment - the price, of course varying depending on the time and place of purchase (don’t forget that we price match!). It’s easy enough to work out: simply divide the total light output (PPF) of each fixture by the price - the higher the number, the more photons you’ll be getting for each £1 spent.

Can’t I just replace the bars by buying them separately?

One approach to upgrading from a 2.7 to a 2.9 would be to purchase the individual bars from us (available soon) and upgrade in two stages. Lumatek recommend replacing a minimum of three bars to avoid disparities in input current. Some users - especially those with quantum light sensors - may even find this approach optimal, as using a mixture of bars in various configurations would give the grower more control over intensity and spread.

Again, for those existing Zeus 600w Pro 2.7 users, the extra yield provided by the 10% light increase from these fixtures will only apply if their light is already being maximised. If, for example you have a single 2.7 in a 1.2m tent and are hanging it higher than 18” from the canopy in full bloom and having to add heat to the space while it is on, then improved fixture efficacy will do little more to save electricity and improve yields than lowering the position of your existing light will.



As you've read, from our testing we were able to confirm that the Zeus 600w Pro 2.9 does in fact, produce about 10% more light per-watt than the Zeus 600w Pro 2.7. Whether this new advantage can be maximised by the grower to achieve either an increase in yield or a decrease in overall electricity consumption is certainly achievable, but will come down to the grower's own situation and experience. It's undeniable that Lumatek’s new Zeus 600w Pro 2.9 is a well-built, robust LED grow light that currently leads the efficiency evolutionary arms race within the UK market. Combine these performance figures with its very reasonable RRP and 5 year warranty, elite growers looking to be ahead of the efficiency curve in 1.2-1.5m tents and large rooms will certainly appreciate the extra light that this fixture has to offer.


Product Links

Lumatek Zeus PRO 2.7

Lumatek Zeus PRO 2.9