Flowering light requirements for 4x4?

[Aero808]

Hello everyone,

I've been doing some googling (uh oh!) haha.

I'm wondering if my setup will provide adequate power during flower? I'll be running a 400w hps in an aircooled reflector. The reflector is designed to provide uniform light to a 4X4 area. I'll also have 3 50w led grow bars. I'm thinking I'll turn them horizontally to make full use of them and shine them directly at the scrog canopy.

Any success stories flowering a 4x4 area with a 400w hps? What should my realistic expectations be?

How much difference would jumping up to a 1000w hps make in yield? Is it overkill for a 4X4?

Thanks for reading! Cheers!

 

[Blew Hiller]

I don't have any experience with HPS, but @PurpleGunRack seems to know the score on lighting.

 

[Chris Scorpio]

I ran a 600w HPS in my 4x4, think a 1000w may be a bit much unless it's dimmable

600w worked great, just too much heat for where I live

 

[Aero808]

Hi Blew Hiller, thanks for helping out. Looking forward to seeing what Purple has to say.

I ran a 600w HPS in my 4x4, think a 1000w may be a bit much unless it's dimmable

600w worked great, just too much heat for where I live

I was eyeballing a used 1000w lumatek adjustable digital ballast. I've heard that taking a 1000w bulb and dimming it reduces it's lifespan though?

Were you scrogging when you used the 600w?

 

[Chris Scorpio]

Never scrogged

That balast would be great, I used to dim mine down to about 400w, was a % not actually 400w, worked real well

 

[PurpleGunRack]

How about adding another 400w HPS to what you already have


Basically you need 1000w HPS per m2 to optimally flower cannabis, not possible in many practical applications due to heat issues, but it paints a picture of how much light is needed for full saturation, of course less will do just fine.

I know a few guys who've grown with 400w HPS in 4x4 and it will work, but the guys with 600w HPS in 4x4 do a lot better for sure.

If you grow ScroG you're better off with better spread and less penetration, so replacing your current gear for a 1000w HPS might be counter productive.

 

[Aero808]

That sounds like good advice. Thanks Purple

 

[Mars Hydro]

I was gonna say, if you add one or two 50w led side lights, that might also help, so one 400w HPS above, and around 200~250w led compensate lights, I guess should also be enough, and might give you better coverage.