well i have a 400 wat hps super deluxe lamp and my plants are around 12 days old i no u should use mh first but is not a option at the moment will my plants be able to grow under it i am using lowrider2 if that helps at all so it is auto flowering and has such a short life cycle i was not sure any help would be appreciated.
I have a 400W MH, the type that is compatible with a HPS ballast, and a HPS ballast and ignitor. If I want to use HPS I just buy a HPS bulb and screw it in. Much better than trying to use HPS throughout.
If you absolutely don't have the option to use a MH, you'll be fine with the HPS from start to finish. You asked if your plants will be able to grow under the HPS... have they not grown a wink in 12 days or what?
There is only one difference between a MH ballast and a HPS ballast. The ignitor. You can run a MH bulb half ass in a HPS ballast but you can't run a HPS bulb in a MH ballast because a HPS bulb needs and ignitor to run and a MH bulb doesn't. I use a MH bulb to check if a HPS ballast's Ignitor is broken at the grow shop where I work part time fixing and rewiring voltages of new and used ballasts. If a HPS light wont work but a MH light will in a HPS ballast then I know to replace the ignitor. If you add an ignitor, of the appropriate size, to a MH ballasts circuit you have just turned it into a HPS ballast. Likewise if you remove the ignitor from a HPS ballast and rewire the circuit properly you have just turned a HPS ballast into a MH ballast. There are ballasts that will with a flick of a switch run either a MH or a HPS bulb and that's how it is done. One side of the switch uses the ignitor and the other side of the switch bypasses it. I do not suggest that anyone who doesn't have a comprehensive understanding of electricity undertake any rewiring or modification of any ballast or even outlets for that matter as it will more than likely lead to their house burning down. To answer merlinz1's question I agree with TitaniumFox's statement. Personally though I use a high output T5 rig to get my plants to a foot and a half high before I put them into the flowering room but hey that's just me and you should grow whatever way gets you the best results. I like the better return so that's what I do.
That statement doesn´t agree with Helvar´s web site. They are the biggest European manufacturer of ballasts of all kinds. Their wiring diagrams for MH ballasts shows an ignitor for each type. My own ignitor has a power specification for both MH and HPS lamps. All I can say is, confuson apparently reigns.
You can use a hps through the whole grow. Everyone says the plants will stretch and all of that, but from my own experience, my plants just become bushes as soon as they are put under the hps. I usually veg my plants right under t-8's (like 2 inches under the light), and when they are about 2 feet tall they go under the hps, where they almost immediately explode with new growth. I have a mh conversion bulb I have never used because I always have the hps(s) on 12/12. If I started out with all new plants, I would use it. But since i grow different strains, I always have a bunch of indicas that are finished quickly, and a bunch of sativas that seem to take forever to be done.
dude wants to know if he can use HPS all the way through not chat about irrelevant technical stuff lol OP - yes you can easily grow decent weed with just an HPS - check my gallery - everything in there was grown SOLEY under a 600w HPS
thank u every one for ure in put ok i can run a mh through my ballast its just i live around 3 hours from the nearest light shop and i work 12 hour days so its a bit hard for me to get down there for at least 2 weeks so it will have to do for now but yes they are sprouted and are 12 days old today but seem to be streching but i did start them under cfls that were a bit high or well there still standing and ounce again thank u all peace
you can always combine 2 or 3 6500K CFL's for VERY cheap with your HPS if you are worried about stretch
The answer is that he can, at a pinch, but will get better results vegging with MH and flowering with HPS. So comparisons about the requirements of MH and HPS lighting systems are totally relevant, IMHO.
Isn't it kind of subjective, really? I mean... I grow solely with a 400W HPS, and only have to veg for 10-14 days. There is absolutely no reason why I'd need to invest in a MH bulb when the plants I grow are already as bushy as can be before I switch over to 12/12. I've only experienced dense bushy green growth using an HPS throughout the grow. So my answer isn't... "yes, it will be decent but would be better to veg with a MH" ...my answer is "Yes, absolutely... in fact, ditch the whole MH is better to veg with all together. You can grow fantasic herb with just HPS bulbs" Just my 2c
I remember reading unscientific reports on OG about yield differences between MH/HPS and HPS/HPS. There were just so many variables, I don't think anybody reached a solid conclusion, but the people in favor of HPS for a full grow were really outnumbered (obviously). Anyway, the plants in your grow are gorgeous smoove.. I'll point people there when they ask about HPS results from start to finish.