LED light recommendation for 6.5 x 6.5 tent

I’m a new grower and want to set up a 6.5 x 6.5 grow tent.
Planning on planting 9 plants and using a scrog setup. I have looked at black dog led lights but they are pricey and there seems to be better technology out there. If someone could recommend a LED setup that would be great.
I’m intending to supplement with CO2 gas and would need a sufficient light system.

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That space is almost 4m². To justify using co2 you would be looking for total flux of around 4000 umols/s. I’m not aware of a single fixture that will do that. Most of the bigger led fixtures are around 1800 umols/s and not shaped well for your application.

You are correct about the black dog lights, even if you had unlimited budget that’s not where you want to spend your money. To get into good leds for what you’re looking to do won’t be cheap regardless, but i would shoot for more like hlg, or chilled tech and try to find 4 smaller fixtures that will meet requirements. Or, 4 600 watt hps lights would do that space well.

Depending on what you come up with, you may want a dedicated controller for this. At least keep in back of your mind that it may require some electrical work.


Hi dbrn32, thank you.
Wouldn’t 2 x 1000 watt or 3 x 750 gavita lights also suffice?
Would it not overheat the room or would I need to cool the room with something more than extraction fans?
HPS is great for flowering but if I understood properly, not ideal for growth, or would it not really matter?

Would I be able to build a LED that could maximize the growth and flowering at 4000 umols/s and what would I need?

Sorry for all the questions, I don’t know my way around lights and am being cautious when it comes to buying them.


Two de gavita would get there, standard 1000 isn’t ridiculously higher than a good 600. I think last sphere report I’ve seen on hortilux bulb was about 1280 umols/s measured 350nm-750nm. Their 600 is about 1000 umols/s. Where you would run into is problem getting balanced coverage with two or 3 fixtures in a square space. You don’t necessarily need to have balanced par levels, but it sure makes things easier and results are typically better. If you were to go hid, I would think the 4 600’s is best option. They are usually most efficient and that setup would check the other boxes as stated. I would absolutely plan on air cooled hoods, that should cover most of potential heat issues.

Going with leds, the big fixtures would probably be better than running two big hid lights, but present similar issue. They are usually about 40" squared or less, and you would be asking to cover almost 80". The good news here is that stepping to 4 lights gets you into smaller and less expensive fixtures. Could do something like 4 hlg-350r or similar.


Thank @dbrn32, the pricing for 4 x 600 gavita pro se and controller is reasonable and would seem worthwhile.

So I should be fine using these lights both for growing and flowering, is that correct?

I see these lights come with their standard hoods.
Does this mean I need to exchange these hoods with air cooled reflectors or just keep them as is?

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You don’t necessarily need gavita. To my knowledge their 600 watt rig isn’t much different than the rest. They are more know for de tech. I would shop around some and see if you can find reasonable air cooled setup before just buying gavita and replacing hoods. Hortilux makes quality bulbs, and there are others too. I have been out of hid game for a while though, maybe someone like @Hellraiser or @peachfuzz could help more there.

I never had any problem vegging with hps. Node spacing is a little longer, but plenty acceptable. Lots of people prefer to veg with mh bulb over hps though, so you would probably have to decide for yourself. If you get digital ballast bulbs are usually interchangeable. I don’t care for the digital ballasts much, but they are said to be better now than the models I have experience with.


Maybe hold off on that co2 and get this setup dialed in


Well I have a flower room …
That’s 12’ x 16’ with three flower tables that are 4’ x 5’ and each table has its own 600 watt hps bulb with a magnetic ballist and an 8" xxxl sunsystem air cooled hood and one 8" 750 cfm extraction fan that pulls air from either outside and through the hoods and vents back outside or pulls air through the room and then through the hoods and vents back outside…
If I’m running co2 then the air to cool the hoods is pulled from outside through the hoods and then vented back outside and when I’m not running co2 , the air is pulled through the room and through the hoods and then back outside…
I usually only run co2 for the first 3 weeks from light flip , after that I think its pointless…
I find that magnetic ballist’s are more reliable and alot less expensive than digital and bulbs tend to last alot longer , although they do create a little more heat…
I believe my ballist’s are sunsystem also…
I’ll have to check…
When I bought them , my hoods were 200 bucks a peice and my ballist’s were like 110 bucks , so not really expensive…
Bulbs are about 65 bucks depending on were you get them…
Lots to think about…
If my room wasn’t set up so well for how I do things already , I would probably look into LEDs , only because I’ve been hearing and seeing alot of good things about them , but I’m not 100% sold on them yet and my room is dialed in so good that I’m not ready for the hassle of changing everything up just yet… :+1::wink:


My experience as well. Never had a magnetic ballast go out but lost digital ballasts quite regularly which prompted me to move to LEDs.

I would not get the expensive DE gavitas for a grow tent, their design with the ballast stuck to the reflector makes them about impossible to air-cool, they are better for open grow rooms with AC to control temps. I’d just go with regular 600 watt MH/HPS with air cooled hoods for a tent and your gonna want to exhaust that hot air somewhere other than the room the tent is in.


I agree with what @Hellraiser said , you definitely don’t want a ballist thats attached to the hood that isn’t air cooled…
A friend of mine used the 1000 watt de gavitas that weren’t air cooled and those suckers got so danm hot , they were basically pointless to use , he had to have a massive ac system just to keep temps kinda in range and he was in a room , in a tent I would be worried about a fire with any hood that wasn’t vented… :wink:


O thank you very much, for the quality info.
Would LUMii magnetic ballasts be worthwhile? I don’t have much variety where I reside.
Putting together a ballast, air hood and the bulbs isn’t much of a hassle, and comes cheaper then the gavita lights.


Sure. have not heard anything bad about them.


Gavita is just way over priced everything from its hids to leds your paying for the name… 2 hlg scorpions will get you there as well also I use a single hlg 600 v2 rspec per 5x5 area and it gets me up to co2 lvls the newer 600s are more evenly spread and 2 of them in a 6 5² is also ample I’d say your easiest route without much more cooling and ducts ran and having to worry about a sealed system to also cool fixture independently 2 hlg 600s would be pretty easy to get in there… the new 600s are square the v2s are more rectangle and would probably fit space better then 2 squares … the v2s arenlike 650 to 700 plug and play

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You have a lot of great, experienced growers giving you sound advice.

I’m a new grower. I just started my 4th grow.

So, for what it’s worth, here’s my $.02.

First, a little about my grow. I’m in a 3x3 with 2 240w DIY kits from HLG. It’s total overkill for my tent.

The first thing that came to mind when I read your first post is, “6 of my lights would rock his tent.” I would measure out and hang them evenly spaced.

After reading I see that you’re interested in going HID. I totally respect HID. They’ll grow great bud.

Look on Craigslist and eBay. You’ll find old magnetic ballasts dirt cheap. My local grow shop has a shelf full of used ballasts that he is almost willing to give away to make room for new LED. You’ll find lots of bargains online.

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Thanks to all for the great feedback. I haven’t completely opted for HPS, the HLG SCORPION DIABLO looks really good. And I would love to order two and set them up in the tent.
However they are pricey and shipping and import VAT make it more expensive. But it sure is an energy efficient rig in the long run and that is appealing.

The HPS would be cheaper initially for me, if I could rig my own LED and get similar results to the HLG S D for a lower price that would even be better, but I’m assuming it might cost just as much getting all the components imported.
Secondly, if I have warranty claims, these would be difficult to sort out quickly and I’m unsure if these would be sorted in a timely manner.

@peachfuzz or @Hellraiser … i cant recall for sure but there was an interchangeable aspect of hids… I used em in the begining I had a 150 hps 175Mh and a 400 hps…it was an ipower 400 eith dimmable ballast… for some reason I thought hps ballast only used hps bulbs unless it’s an interchangeable and specified it is…makes sencen to , because alot of ppl say to go MH for veg … I’m assuming because it’s a much sharper blue but with my acquired knowledge over the last couple years… useable light is useable light … but I had 400 watt hps bulbs that were In 4000k very blue looking … with alot less green in it … I dont see the difference being in veg …light Is not nearly as important as flower … really what my stoned ramble is asking is are all hid ballast hps to mh interchangeable… but it must be the same wattage rating right? … what would be your purpose to go MH to HPS and do you think it would he better than 4000k hpsfor veg purpose… indent see the point :thinking::thinking::thinking:

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I see HLG has their 550 RSpec in their refurbished section for $599. Two of those would work great. Not sure about the warranty but it would be worth looking into

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2 squares inside 1 square would be hard to position good because 550s are for a 4x4 … if you out side by side the 1 foot on each side won’t be lit the best I’d say 4 320s will be optimal and you can position them in a 6.5² much more evenly u can use them as quadrant which would he. Sweet

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Hi @dbrn32, what’s your take in getting two HLG SCORPION DIABLO for my grow space?

To veg on 18 hour schedule it would probably fine on ambient co2. You would want more light to flower though. And even more light on top of that to justify supplementing co2.

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