HLG 600 R-Spec vs Spider Farmer SF7000 LED Comparison

The short answer

For a flowering room in a 5 by 5, the HLG 600 R-Spec is the fixture to put over the canopy. That verdict is narrower than it sounds, and it is worth saying exactly what it rests on, because two of the three arguments people usually make for it do not hold up.

It does not win on raw output. The SF7000 publishes 1,786 µmol/s against the HLG's 1,522, and claims 2.8 µmol/J against 2.60. Taken at face value that is a 17 percent photon advantage. It does not win on running cost either: measured at the wall the two fixtures sit within about eight watts of each other, which is noise over a season.

What it wins on is the spectrum and the evidence. The R-Spec board is weighted toward red and deep red, which is what a 12 hour flowering photoperiod rewards. And the HLG's photometric claim is backed by a commissioned laboratory report that publishes the full PPFD grid at two mounting heights — a document you can read and check. The SF7000's figures are manufacturer claims that have moved over time, and the one independent test of the fixture did not reproduce them.

That is the whole case. If centralised dimming across a row of fixtures is what your room needs, the conclusion flips, and the section on control explains why.

The two fixtures side by side

Every row below is a figure both manufacturers publish. Where only one of them states a number — amperage, recommended hanging height, daisy-chain limits — it is handled in the prose instead, because a comparison row with one side blank is not a comparison.

The weight gap is larger than it looks on the page. Fifteen pounds against twenty-eight is the difference between one person hanging a fixture on ratchets and two people doing it, and in a tent it is the difference between hanging from the top bar and hanging from the frame. Check what your tent is rated to carry before you commit, particularly if you plan to run two fixtures.

One disagreement is worth naming. Retailer spec sheets for the SF7000 do not agree on the diode. Some list Samsung LM301B; at least one lists Bridgelux 3030. Those are different parts with different efficacy curves, and no retailer page resolves it. The HLG's diode is stated consistently everywhere as Samsung LM301H with 660 nm deep red.

Where these numbers come from

This is the section that decides the comparison, and it is the one most spec-sheet shootouts skip. Two fixtures can print photon counts in the same font and mean entirely different things by them, because one number came out of an accredited laboratory and the other came out of a marketing department.

The HLG 600 R-Spec's 1,522 µmol/s traces to a photometric test report commissioned from an independent light laboratory, and that report publishes the complete PPFD grid at both 24 and 30 inches. Measured input power in that test was 596.80 watts against a 600 watt rating. You can read the grid, check the arithmetic, and see where the light actually lands. The chart further down this page is that grid.

The SF7000's figures are manufacturer-published, and they have moved. The fixture has at various points been specified at 1,681 µmol/s and at 1,786, and the efficacy claim has carried values that do not reconcile against the manufacturer's own photon and wattage figures. When a company's two published numbers cannot both be true, that is worth more than either number on its own.

One independent party has put the SF7000 on a meter. In a test run in May 2021 across a 60 by 60 inch area at 25 inches, the measured draw was 605 watts against the 650 watt rating, average PPFD came in at 569.1 µmol/m²/s, the hot spot reached 1,000 and the low point 339. Light distribution was graded C-plus. That is a competent result for the money, and it is not the fixture the spec sheet describes.

None of this means the SF7000 is a bad light. It means the two claims are not the same kind of claim, and a grower spending several hundred dollars is entitled to know which one has been checked. Our piece on avoiding getting ripped off on LED grow lights goes further into how photon claims get inflated.

PAR across a 5 by 5

A footprint rating tells you where the manufacturer is willing to draw a box. A PPFD grid tells you what the plants in the corner of that box actually receive, and the two are rarely the same story.

Read the corners first. At 30 inches the centre of the HLG grid reads 678 µmol/m²/s and the corner reads 93, which is about fourteen percent of the peak. The average across all 121 points is 306. The same report measures the fixture at 24 inches, where the centre rises to 957.50 — raising intensity substantially for eight inches of height.

These two grids cannot be compared directly, and anyone who stacks them side by side is misleading you. One is measured at 30 inches and the other at 22. Eight inches of height is an enormous difference in PPFD, and it flatters the lower chart on every single cell. The honest comparison is the shape, not the magnitude.

On shape they are near twins. The HLG's lowest point is 30 percent of its average; the SF7000's is 29 percent of its. Both fixtures concentrate light in the middle and give up roughly the same proportion at the edge. The independently measured SF7000 grid, taken at 25 inches, actually comes out more even than the manufacturer's own — a low of 339 against an average of 569, or 60 percent.

The practical reading: at the heights these grids were taken, neither fixture delivers a flowering-grade average across a full 5 by 5. A flowering canopy generally wants to sit somewhere around 700 to 1,000 µmol/m²/s, and getting there with either fixture means hanging lower, accepting a smaller footprint, or running two lights. That is not a criticism of either product. It is what a single 600 watt class fixture does over 25 square feet.

Spectrum and diodes

Photon count tells you how much light arrives. Spectrum tells you what the plant does with it, and in a flowering room weighted toward 12 hours of light a day, the distribution across the red end is where the yield argument actually lives.

The HLG 600 R-Spec runs higher relative intensity in red around 600 nm and deep red around 660 nm. The SF7000 peaks higher in the blue region around 450 nm. Both are full spectrum white fixtures and both grow plants perfectly well; the difference is where the weight sits.

That weighting matters most in bloom. Red and deep red drive reproductive growth and flower biomass. Blue governs vegetative structure, internode spacing, and contributes to resin and terpene development. In a flowering photoperiod capped at 12 hours, the daily light integral is fixed by the clock, so every photon should be doing the job the stage calls for. A board tuned toward red returns more flower per hour of light. Blurple, red and full-spectrum LEDs compared covers the spectral argument in full.

The second chart is the more useful one. Put the HLG curve next to commercial fixtures from other manufacturers and it lands close to the industry consensus for a flowering spectrum: strong red and deep red, enough blue to hold plant structure. The SF7000's cooler balance sits further from that group.

On diodes, the HLG has the clearer provenance. Samsung LM301H with dedicated 660 nm deep red is stated consistently on every listing, and Samsung horticultural diodes have a long record for output stability over time — which matters, because a fixture that loses photons in year three costs you yield you will never attribute to the light. The SF7000's diode is listed inconsistently across retailers, and that is a harder thing to plan around.

Dimming and control

This is the section where the verdict can legitimately flip, and it depends entirely on how many fixtures you are running and whether anything else in the room is already automated.

Both fixtures dim. The HLG 600 R-Spec dims from 60 to 600 watts through its driver, which is a genuinely wide range — enough to take the same fixture from propagation through to peak flower without swapping hardware. The SF7000 supports 0 to 10 volt control and can be daisy-chained, with retailers quoting limits from 15 fixtures up to 60.

For one light over one tent, that difference is close to meaningless. You set the dial and you walk away. For a room running eight or twelve fixtures in a zone, it is the whole argument. Walking a row of lights and matching dial positions by hand is how zones end up uneven, and the grower rarely finds out until the canopy tells them two weeks later.

If centralised control is where you are heading, it is worth looking past both of these at the fixtures built for it. The Tomahawk 720 and Tomahawk 650 with GrowFlux wireless take control off the fixture entirely, and the GrowFlux access point runs up to 200 devices on one mesh — all three are in the table below. That is a different budget and a different scale of room, but it is the honest answer to the control question.

What each one draws

Rated wattage and measured wattage are different numbers, and on these two fixtures the gap between them is large enough to erase an advantage that looks solid on a spec sheet.

Rated, the HLG draws 600 watts and the SF7000 draws 650. That is a 50 watt gap and it is the basis of most running-cost comparisons between them. Measured at the wall, the HLG came in at 596.80 watts and the SF7000 at 605. Eight watts. Over a year of flowering cycles that is a rounding error.

Multiply the kilowatt hours by your own rate. Rates vary by a factor of three across the United States, so a figure printed here would be wrong for most readers the day it was written. What the table shows regardless of rate is that on measured draw the difference between these two fixtures is about three kilowatt hours a month at a 12 hour photoperiod.

The dimming range is the bigger lever. A fixture that runs from 60 watts means a propagation stage costing a tenth of what a flowering stage costs, on the same hardware. LED versus CMH on cost runs the same arithmetic against the older technology, if you are still weighing that.

Hanging height changes everything

Of every variable in this comparison, the one with the largest effect on what your plants receive is not the fixture. It is how far above them you hang it, and it is the one variable entirely under your control.

The HLG's own laboratory grid makes the point better than any argument could. At 30 inches the centre of the footprint reads 678 µmol/m²/s. At 24 inches, the same fixture, the same room, the same meter, the centre reads 957.50. Six inches of chain is worth roughly 280 µmol/m²/s at the centre of the canopy.

That cuts both ways, which is why the manufacturer gives a range rather than a number. HLG specifies 28 to 36 inches above the canopy, and about 48 inches for veg, where the 7 by 7 footprint comes from. Hang it at 24 inches and you get the intensity, along with a tighter footprint and a real risk of light stress on the tops. The right height is the one that puts your target PPFD on the canopy you actually have, not the one that produces the best chart.

The SF7000 is generally run closer, and that is a genuine advantage in a low-ceiling space. A tent with limited headroom, a basement with ducting overhead, a closet — in those rooms a fixture that performs at 22 to 25 inches solves a problem that no amount of photon output can. Hanging a grow light in a closet covers the constraint in detail, and five common LED setup mistakes covers what goes wrong when the height is picked by eye.

The rest of the HLG line

The 600 R-Spec sits in the middle of a range that runs from a 65 watt veg board to a 720 watt commercial fixture with wireless control. If the 5 by 5 flowering footprint is not quite your room, the answer is often another fixture in the same family rather than another brand.

Two rows deserve a second look if you came here for a 5 by 5. The Scorpion Diablo in the table above puts 2,130 µmol/s over the same footprint from six boards — forty percent more photons than the 600 R-Spec, which is the honest route to a flowering-grade canopy average over 25 square feet. And the 350R Diablo posts 3.11 µmol/J, the highest efficacy in the range, which makes two of them over a 5 by 5 a serious alternative to one larger fixture.

Deeper reviews of the line sit in the HLG 550 V2 R-Spec, B-Spec and ECO comparison, the 350R against the Mars Hydro FC 3000, and the 225W Elite unboxing. The full brand page is Horticulture Lighting Group.

Which one belongs in your room

The comparison resolves differently depending on three things: how many fixtures you are running, how much headroom you have, and whether flowering yield or vegetative structure is what you are optimising for.

Notice how many of those rows point somewhere other than the two fixtures in the title. That is deliberate and it is the useful part of running this comparison properly: a head-to-head between two products is only the right question if one of those two products is genuinely the best fit for your room, and quite often neither is.

The warranty question is worth settling before you commit either way, because it varies more between brands than almost any other term. The LED grow light warranty comparison lays the terms out side by side.

Getting a 5 by 5 right

Most of the disappointment that gets blamed on a fixture comes from one of four things, and none of them is the photon count. These apply to either light in this comparison and to every other fixture at this size.

The fourth point is where the HLG's 60 watt floor earns its keep, and it is a specification most comparisons skip entirely because it does not photograph well on a chart. A fixture that covers the whole crop cycle is one fixture rather than two.

If the room is smaller than a 5 by 5, the sizing changes completely — LED picks for small tents and closets covers that end, and the LED grow light FAQ handles the questions that come up once a fixture is hung.

FAQs

The questions below come up most often on this comparison, and several of them have answers that contradict what the spec sheets imply.

Which fixture produces more light?

On published figures the Spider Farmer SF7000 does: 1,786 µmol/s against 1,522 for the HLG 600 R-Spec. The qualifier matters, though. The HLG figure comes from a commissioned laboratory report that publishes its full measurement grid, and the SF7000 figure is a manufacturer claim that has carried different values at different times. More photons on paper is not the same as more photons on the canopy.

Does the HLG 600 R-Spec really cover a 5 by 5?

It covers a 5 by 5 in the sense the industry uses the phrase, which is that light reaches all of it. At the 30 inch height in the published grid the centre reads 678 µmol/m²/s and the corners read 93, averaging 306 across the area. For a flowering canopy that wants 700 to 1,000, that means hanging lower, accepting a smaller usable area, or running two fixtures. The same caveat applies to every single fixture at this wattage.

Is the efficacy difference worth anything?

2.60 against 2.8 µmol/J is about an eight percent difference on paper, and on measured draw it narrows further. Across a 12 hour flowering day it is not the number that will decide your harvest. Spectrum, canopy height and consistent environment all move yield more than eight percent of efficacy does.

Can I daisy-chain the HLG 600 R-Spec?

It dims from 60 to 600 watts through its driver, which covers a single fixture comfortably. For centralised control across several fixtures, the Tomahawk models with GrowFlux wireless are the ones built for it, and they take the control off the fixture entirely.

How high should I hang either of these?

HLG specifies 28 to 36 inches above the canopy for flower and around 48 inches for veg. The SF7000's published grid is taken at 22 inches and the independent test at 25. Treat all of those as starting points and set the final height with a meter on your own canopy.

Which one is better for veg?

The SF7000's cooler, bluer balance suits vegetative growth slightly better, and blue light tightens internode spacing. But a fixture bought for flower and dimmed for veg is usually the better economics than two fixtures, and the HLG's 60 watt floor makes that practical.

The bottom line

For a flowering canopy in a 5 by 5, the HLG 600 R-Spec is the fixture we would put over the plants, and the reason is narrower and more honest than the usual spec-sheet argument: a spectrum weighted where a 12 hour photoperiod needs it, and photometric data that has been through a laboratory and published in full.

The Spider Farmer SF7000 posts higher numbers and is a capable fixture, particularly in a room with limited headroom where it can be run at 22 to 25 inches. Its case is weakened not by its performance but by the state of its documentation: figures that have changed, an efficacy claim its own arithmetic does not support, and a single independent test that measured a different light from the one described.

What the data from both fixtures agrees on is more useful than the winner. A single 600 watt class fixture does not light 25 square feet to flowering intensity. It lights the middle well and the corners poorly, and that is true of both of these and of everything else in the class. Plan for two fixtures, a smaller usable canopy, or a larger light such as the Scorpion Diablo, and the room will do what you expected.

If you want help matching a fixture to a specific footprint and ceiling height, call us or leave a comment below. Tell us the tent size, the headroom and how many zones you are running, and we will tell you what we would hang.