These two are our best sellers, and it isn't close. Week in, week out, more of them go out of the door than anything else we stock.

That tells you something straight away. Neither of them is a bad buy. So this isn't a hunt for the dud. It's about which one suits you.

Here's the short answer.

The Mars Hydro TS1000 puts out more light, and it's the one to pick if you want the most growing power for a 60 to 70cm tent.

The Spider Farmer SF1000 is more efficient, a little cheaper and a little lighter, and it slots into Spider Farmer's GGS smart system.

The numbers

These are the manufacturers' own figures. For the SF1000, that's what the guys at Spider Farmer tell us. For the TS1000, it's Mars Hydro's spec sheet.

Spider Farmer SF1000

• Power: 100W
• Light output (PPF): 249.2 µmol/s
• Efficiency: 2.5 µmol/J
• Coverage: 2 x 2 ft (about 60 x 60cm)
• Diodes: Bridgelux, upgraded for 2026
• Warranty: 5 years

Mars Hydro TS1000

• Power: 150W
• Light output (PPF): 343 µmol/s
• Efficiency: 2.3 µmol/J
• Coverage: 2 x 2 ft for flowering, 2.5 x 2.5 ft at most
• Diodes: Bridgelux
• Warranty: 5 years

So the TS1000 makes roughly 38% more light. It also draws 50% more power to do it. That's the whole contest in two lines, really.

Light output: TS1000 wins

More light, within reason, means more growth. In a 60cm or 70cm tent, the TS1000 has enough in hand to run at around three quarters power and still do the job properly.

That headroom matters in winter. When your loft is cold and the plants are sulking, it's nice to know there's more on the dial.

The SF1000 is no slouch. Plenty of people have grown superb first crops under one. But in a 70cm tent at the flowering stage, it's working hard, and you'll want it near full power for most of the grow.

Shop the Mars Hydro TS1000 LED Grow Light

Efficiency: SF1000 wins

Efficiency is how much light you get for each watt. The guys at Spider Farmer tell us the SF1000 runs at 2.5 µmol/J. Mars Hydro says 2.3 for the TS1000.

That's a small gap, and both are miles ahead of the old orange HPS lamps. On a 12/12 flowering day, the SF1000 costs less than a can of Red Bull a day to run. So does the TS1000. The difference between them over a day is about the price of a Freddo.

Here are the sums, at 26.32p per kWh:

• SF1000: 100W x 12 hours = 1.2kWh, about 32p a day
• TS1000: 150W x 12 hours = 1.8kWh, about 47p a day
• The gap: 50W x 12 hours = 0.6kWh, about 16p a day. One Freddo.

Where the SF1000 really scores is heat. Less power in means less heat out, and in a small tent in a British summer that's worth a lot.

Shop the Spider Farmer SF1000 LED Grow Light

Build and design

They look different because they are different.

The TS1000 has a reflective hood around the board. Mars Hydro has a patent on the shape, and the idea is to catch light that would otherwise spill sideways and push it down onto the plants. It's a bit bigger, at about 38 x 34cm.

The SF1000 is a flat, open board with a big aluminium heatsink on the back. There's no fan, so it's completely silent. Ours weighs in at about 1.9kg, which means it hangs from almost anything.

Both are dimmable. Both can be daisy-chained if you want two in a longer tent.

Smart control

This is where your choice might make itself.

The TS1000 comes in two versions on our site, Manual Control and iConnect Bluetooth Control. The iConnect version comes with a little stick that plugs into the dimmer box, so you can dim and schedule the light from the MarsPro app. It's only the light, though. It won't run your fans.

The SF1000 works with Spider Farmer's GGS system. The guys at Spider Farmer tell us the GGS Controller runs their SF, SE and G series lights, apart from the SF1000D, SF300 and SF600, so make sure it's the standard SF1000 rather than the SF1000D. If you're planning a full smart tent, with fans and sensors all reading from the same app, Spider Farmer is the neater route.

Our GGS vs iConnect guide goes into all of this properly.

Read: GGS vs iConnect Smart Grow Kits

Price

The SF1000 is the cheaper of the two on our shelves. The TS1000 Manual is a few pounds more, and the iConnect version is ten pounds more again.

Work it out per unit of light, though, and the TS1000 gives you more for your money. The SF1000 gives you the lower bill and the cooler tent.

Prices change, so check the product pages for today's.

Which tent do they suit?

Both are happiest in a 60 x 60cm or 70 x 70cm tent.

• 60cm tent: either light. The SF1000 is the better fit here, and you won't be wasting light on the walls.
• 70cm tent: the TS1000, if you're flowering. The SF1000 will do it, but it's at full stretch.
• 80cm or bigger: neither. Step up to an SF2000 Pro or an FC-E1500.

Shop the Spider Farmer SF2000 Pro LED Grow Light 200W

Shop the Mars Hydro FC-E1500 LED Grow Light

If you want everything in one box, the SF1000 Smart Grow Tent Kit pairs the light with a 70cm tent, a GGS fan and a filter.

Shop the Spider Farmer SF1000 Smart Grow Tent Kit

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Our verdict

If you want the most light for a small tent and don't mind a bit more heat, buy the TS1000. Get the iConnect version if you fancy running it from your phone.

If you want something cool, silent and frugal, or you're building a Spider Farmer smart tent, buy the SF1000.

There's no loser here. It's a bit like choosing between a Golf and a Focus. Both will get you there, and both will still be going long after the excitement of the new car smell has worn off.

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