In my opinion HPS (High Pressure Sodium) is the best for your money no matter what, t5 fluorescent for cloning but yeah... Here is a scale on light size and i also got a site with 10% off all products... they are trusted...
___________________________________
| Wattage | Coverage | Height above plants|
|________|_________|________________|
| 150...... | 2x2 sq ft.. | 2 to 3 feet........... |
|________|_________|________________|
| 175...... | 2x2 sq ft.. | 2 to 3 feet............ |
|________|_________|________________|
| 250...... | 3x3 sq ft.. | 2 to 3 feet............ |
|________|_________|________________|
| 400...... | 5x5 sq ft.. | 4 feet................... |
|________|_________|________________|
| 600...... | 6x6 sq ft.. | 4 feet................... |
|________|_________|________________|
| 1000.... | 8x8 sq ft.. | 4 to 6 feet ........... |
|________|_________|________________|
I made the table just for you... NOW FEEL SPECIAL! lol jk
http://www.expresslightbulbs.com/grow-light-hps-grow-lights-c-132_192.html?zenid=d2a7ff224ac9eeeb78d4e9e7a491d6f8
Coupons:
code: ProWebs 5$ off on all purchases, first purchase
code: GetGreen 10% off all purchases 50$ or more
Hope it helps
I think if I had my 400w 4ft away my plants would stretch like crazy and 4-6 for 1000w? this chart is way off imo. I think you will get the coverage you posted with the lights that far away but the plants would be tall and thin for sure. I have my 1000w hps less than 18inches from the tops of my plants
LOL
yea dude HPS makes plants stretch because lots of them lack blue spectrum and even most blue spectrum added bulbs dont put off enough to stop the plants from still stretchin a lil..it just cuts down on it a lot..
The best bet for an autoflower IMO is a Ceramic Metal halide, a Phillips MasterColor (or Master Color, but I think MasterColor) --
They put off pretty good blue and ultraviolet with more intense light from the yellow/orange/red range with a good peak on the 570nm-590nm area of the spectrum.. as you can see in the spectral graph:
Don't listen to that idiot that's trying to make you 'feel special', he's a reseller of that site and he's looking around on here to try and poach a few customers while not getting banned by acting like a user.
Look at the pathetic prices on those..and THAT'S TEN PERCENT OFF?!
Go to E-bay..
If you want to use a retailer and dont need a cooled hood go with insidesun.com they have cheap 250/400w HPS or MH lights -- however they use a magnetic (hummmmmmmming) ballast, however compared to the ventillation fans it is negligible. There's debate about which is safer, but many claim it's digital ballass..
http://www.insidesun.com/Super_Economy_400_Watt_MH_65a26e.item
that's to their $99 400w HPS..
I think the Phillips colormax is meant to run on HPS ballasts..
I am one of those who think it's digital ballasts..
They sell kits on sites like HID hut with an air cooled reflector for the same price as that guy lists for those all-in-one heat machines..
http://www.hidhut.com/catalog/hid-hut-light-kits-c-25_49.html?page=2&sort=2a
They sell a cool tube + 400w MH/HPS digital ballast + bulb for $244 or economy reflector instead for $200..
Those are cheaper digital ballasts and many will reccomend not getting "made in china pieces of crap"..
I don't know what those ballasts are..but I have a made in china piece of crap that looks similar (but is a diff brand I think) and it runs excellent..
It's Welthink brand and I got it on E-Bay for $75 when the guy who runs daystarhid.com was selling them on there brand new for $85 shipped..
(gave him a private offer)
It's worked excellent for me so far..
The case gets a little warmer than my other ballast because it doesn't have a fan..however..IT DOESN'T RELY ON A FAN THAT CAN BREAK! =) I like that..
As far as the heat difference my other one stays 8-12 degrees above room temp and this one stays 15-20degrees (fahrenheit) which is still max 100 deg (i've seen it hit 94f max actually), which isn't hot to the touch or anything.. but warmer than one that relies on a fan.
Fans are pretty reliable though..
But I've had my share not be regarding computer case fans..and these seem similar.
By the way the difference in heat from a digital/magnetic ballast is negligible as far as how much it will heat a room, however magnetic ballasts tend to not have such broad and even heat dissipation so as far as how hot they get to-the-touch on a single point can be much hotter..
A magnetic ballast is said to put out more light/better light than a digital one..some say it's the other way around..
I believe the magnetic does.. but I believe the difference is negligible, and, that in regards to how much light a bulb is going to put out over a 1 year period of 12 hour a day usage I believe the digital will be the winner, as the harsher starting methods of a magnetic ballast causes bulb degradation to happen more quickly..
I hope this helps..
But I bet it's TL;DR
-J