Can i do a 4x2 with one 250w mh light
- Thread starter jonjonnow
- Start date
I would say "not really"... You might be able to get away with a 250w for veg, but for flowering you will need more. A 250w light has a light radius of about a 1.5 to 2 foot area... so it would be good to cover about 1/2 of your 2x4 grow area, but to spread the light across all 4', you would need 2 lights to get the best results...
Hosebomber
New Member
You want to shoot for at least 50 watts per sq foot with HID. So you would want 400 watts or better. For veg you can get away with 35 watts per sq foot or so but the difference below 40 is noticeable.
Kush Killer
New Member
im running a 400w in a 2x4 ands its not really enuff, if i wasnt redoing my whole setup after this grow finishes, id have got a 2nd 400w
Fuzzy Duck
Well-Known Member
If 4x2 you mean by foot e.g 4' by 2' or even 120cm by 60cm
Then a 250w MH will cover an average of a 2' by 2' / 60cm by 60cm square area if housed in a half decent reflector preferable of a rectangler design this will give you an average 62.5 watts per square foot & thats pretty optimal
Most rectangler reflectors put down a simaler light foot print to shape of it !
So ultimately to make the most out of your grow area 2 x 250w MH will be required to cover total area with reflectors and ballasts to support the lights.
A cheaper option is the Blue spectrum 6500k cfls if gaint versions are aviable which are E40 bayonet fitting a 125w cfl will provide same coverage of 2' by 2' as the 250w MH at a cheaper cost of electricity & ample results for vegging/seedlings/clone/cuttings.
I use a 125w cfl E40 fitting in a 2' by 2' squared area this equates to aprox 31 watts per square foot and a tad shy of 2000 lumen per square foot & in the past have grown seedling/cuttings and vegged plants up to 8 weeks under that same 125w cfl with ample results with my own indica shorter growing strain from cutting to veg to an average height of 18 inches/45 cm in 8 weeks before entering the flowering tent, these results will varie from one strain to another tho.
Another question to the lighting equation is whether you wish to use HPS in the flowering phase & will still require 2 bulbs and reflectors to cover the area this means two ballasts & all of this comes at addittional cost !
Where as cfls do not require ballast as they are in built in the bulb itself saving $$$
If you wish to maintain a MH stance coupled with HPS for flowering, i believe you may find 150w version of each bulb aviable or even a dual spectrum version growlux & sunmaster springs to mind also depending of country of origin & whats aviable.
A 150 w will give you an average of 37.5 watts per square foot
Then a 250w MH will cover an average of a 2' by 2' / 60cm by 60cm square area if housed in a half decent reflector preferable of a rectangler design this will give you an average 62.5 watts per square foot & thats pretty optimal
Most rectangler reflectors put down a simaler light foot print to shape of it !
So ultimately to make the most out of your grow area 2 x 250w MH will be required to cover total area with reflectors and ballasts to support the lights.
A cheaper option is the Blue spectrum 6500k cfls if gaint versions are aviable which are E40 bayonet fitting a 125w cfl will provide same coverage of 2' by 2' as the 250w MH at a cheaper cost of electricity & ample results for vegging/seedlings/clone/cuttings.
I use a 125w cfl E40 fitting in a 2' by 2' squared area this equates to aprox 31 watts per square foot and a tad shy of 2000 lumen per square foot & in the past have grown seedling/cuttings and vegged plants up to 8 weeks under that same 125w cfl with ample results with my own indica shorter growing strain from cutting to veg to an average height of 18 inches/45 cm in 8 weeks before entering the flowering tent, these results will varie from one strain to another tho.
Another question to the lighting equation is whether you wish to use HPS in the flowering phase & will still require 2 bulbs and reflectors to cover the area this means two ballasts & all of this comes at addittional cost !
Where as cfls do not require ballast as they are in built in the bulb itself saving $$$
If you wish to maintain a MH stance coupled with HPS for flowering, i believe you may find 150w version of each bulb aviable or even a dual spectrum version growlux & sunmaster springs to mind also depending of country of origin & whats aviable.
A 150 w will give you an average of 37.5 watts per square foot
Fuzzy Duck
Well-Known Member
Just remember a minor detail !
You never mention height of growing area ?
Please bear in mind a MH/HPS require a greater hanging distance from plant top as not to cause leaf burn/heat stress on average a 250w MH/HPS will be need hung aprox at 12'' to 18'' inch from plant top please include reflector size in final total.
Pot size can also be include into to grow spacing to estimate size of plant which can be grown in limited space !
You never mention height of growing area ?
Please bear in mind a MH/HPS require a greater hanging distance from plant top as not to cause leaf burn/heat stress on average a 250w MH/HPS will be need hung aprox at 12'' to 18'' inch from plant top please include reflector size in final total.
Pot size can also be include into to grow spacing to estimate size of plant which can be grown in limited space !
