SMOKINGBUDDAH
Member
I've heard people vegging there plants under HPS with great results. So lets hear it, what kind of benefit do u get if u veg them under MH compare to HPS? What exactly do u get in return if u veg them under HPS?
Vegging under MH vs HPS ?
- Thread starter SMOKINGBUDDAH
- Start date
J
jasondanzig
the biggest difference i have experienced is a lot of stretching if vegging under an hps. your plant will stay smaller, more compact when vegging under a mh. the mh also gives of more usable light for a plant in the vegetative state.
i have veged under the hps, but i made sure it had a blue/violet spectrum and still had a few problems with the stretch. you can use the hps, but i would recommend using the mh for veg and the hps for flower.
another problem i have experienced, the hps has a much more intense light output than the mh, so you must be careful not to burn your seedlings while under the hps.
i have veged under the hps, but i made sure it had a blue/violet spectrum and still had a few problems with the stretch. you can use the hps, but i would recommend using the mh for veg and the hps for flower.
another problem i have experienced, the hps has a much more intense light output than the mh, so you must be careful not to burn your seedlings while under the hps.
I would use CF for veg and HPS for flower. I use T5 for veg uses allot less power.
DrunkenMessiah
Member
The benefits of running MH, or indeed any other bluer HID lamp, depend on what kind of schedule you're running. I've done low-head-room cytokinin-boosted ScrOG grows that only veged for 15 days. (thats starting from sprouted seeds taken straight out of the paper towels being stuck in the medium) In that sort of situation the benefit of running separate MH lamps would have far and away been outweighed by the massive added cost and complexity.
Indeed! MH gets you a bluer light temperature which makes for bushier, stockier plants. However, to some extent this condition can be replicated via supercropping: the practice of breaking the outer downward-traveling phloem section of the plants' main stems. From a 2-4 day old sprout you can take the main stem section between your fingers and gently squeeze while rotating it back end fowarth. You will feel the phloem give way and crush, there will be a little sound. The plant may lean over and bend a bit, especially on the first treatment, but when done correctly the plant props itself back up and gets a little thicker where you broke it. Wash, rinse, repeat! This eventually result is a massive stem cross-section and very short inter-nodal gaps. This completely halts the streaching of stem sections and it is totally possible to have a healthy plant with the fan leaf nodes closer than one inch to each other on the main stalk. The main stems go on to grow very thick and woody during flower, barking over on the wider sections even on very small plants. (like my earlier-mentioned 15-day-veg babies) You must be careful to only break the phloem; breaking the inner lines, the xylem, leads to catastrophic consequences. The xylem carries water and nutrients up from the root zone and crimping it off completely will kill all plant matter upstream from the break. Usually you won't break it off completely and the upstream growth will slow or stop while the break heals over. This stunted growth is not a deal-breaker, but it is not desirable either. The technique takes a bit of practice, but the resulting vigor and increased nutrient uptake is well worth it. This can be a way of making up for not using MH or floros or some other bluer lamp during veg, but it doesn't solve everything. Granted, I would recommend the technique even if you do use a blue lamp.
Bluer lamps for veg begin to make sense as you get into techniques involving fewer plants and longer vegatative cycles. The colder color temperature makes the plant run a slightly different chemistry that favors storing nutrients away instead of using them for massive growth. Larger fan leaves and stouter stems result and the vegging babies put away tons of sugars. This pays dividends during the flowering cycle, ESPECIALLY if you are running hydro and run the plants on a starvation cycle later own in flower. The stored up saps and auxins reduce shock on the plant during the starve and allow it to resume growth more readily when you re-introduce nutrients. Blue lamps like Metal Halide, Murcury Vapor (mostly outdated) and fluorescents (argued to be too weak, but over-driving and foil-tape reflecting can fix that) can make for a more potent and more productive grow overall when given a long enough veg cycle to pay off, but recent technology has provided an interesting compriamise:
Ceramic Metal Halide bulbs are similar in construction to MH but use a ceramic core and the same ballasts as HPS. CMH bulbs have an extraordinarily white color balance, with even and high-powered output across the range. They have the best output ratings where it counts: PAR, as opposed to Lumens. A lumen rating is a decent comparison between bulbs for their brightness, but lumens are measured in the context of human vision. PAR is a measurement of brightness in terms of the light spectrum that is most efficient for photosynthesis. CMH bulbs will drive dense bushy veg cycles and nugtacular flowering finishes. CMH does have a catch, it can only be run by magnetic HPS ballasts, digital ballasts are incapable of running nearly all CMH bulbs. (there is an exception, too stoned to remember what brand it is, but they are pricey!) Despite its oddities, CMH is an amazing for cannabis, performing well in veg and flower. It even has advantages over HPS for flowering as its super-wide light spectrum means that it has significant ultraviolet output as well. UV radiation (ESPECIALLY UV-B) has a very positive effect on THC content of the flowers. Anyone who has ever treated cannabis plants with a lizard light (floro tube with 5-15% UV-B output) can attest to the way that new trichomes form and existing ones swell up amazingly! (Side Note: lizard lamps kick ass but they WILL cause damage to your plants if over-used. An hour or two a day in the second half of flower, when there are already plenty of trichs present to protect the buds, is pleanty with 32 watt %10 UV-b T8 florescent tubes)
It all depends on your budget really, CMH bulbs are pricier than bog standard HPS, but are priced competitively compared to horticultural HPS or MH. Some growers still swear by super-blue MH during veg and crazy-red HPS during flower, citing the sudden shift in color change throwing the plants into a frenzy. I don't have enough experience one way or the other, but I have witnessed some epic examples of both.
-DM
Indeed! MH gets you a bluer light temperature which makes for bushier, stockier plants. However, to some extent this condition can be replicated via supercropping: the practice of breaking the outer downward-traveling phloem section of the plants' main stems. From a 2-4 day old sprout you can take the main stem section between your fingers and gently squeeze while rotating it back end fowarth. You will feel the phloem give way and crush, there will be a little sound. The plant may lean over and bend a bit, especially on the first treatment, but when done correctly the plant props itself back up and gets a little thicker where you broke it. Wash, rinse, repeat! This eventually result is a massive stem cross-section and very short inter-nodal gaps. This completely halts the streaching of stem sections and it is totally possible to have a healthy plant with the fan leaf nodes closer than one inch to each other on the main stalk. The main stems go on to grow very thick and woody during flower, barking over on the wider sections even on very small plants. (like my earlier-mentioned 15-day-veg babies) You must be careful to only break the phloem; breaking the inner lines, the xylem, leads to catastrophic consequences. The xylem carries water and nutrients up from the root zone and crimping it off completely will kill all plant matter upstream from the break. Usually you won't break it off completely and the upstream growth will slow or stop while the break heals over. This stunted growth is not a deal-breaker, but it is not desirable either. The technique takes a bit of practice, but the resulting vigor and increased nutrient uptake is well worth it. This can be a way of making up for not using MH or floros or some other bluer lamp during veg, but it doesn't solve everything. Granted, I would recommend the technique even if you do use a blue lamp.
Bluer lamps for veg begin to make sense as you get into techniques involving fewer plants and longer vegatative cycles. The colder color temperature makes the plant run a slightly different chemistry that favors storing nutrients away instead of using them for massive growth. Larger fan leaves and stouter stems result and the vegging babies put away tons of sugars. This pays dividends during the flowering cycle, ESPECIALLY if you are running hydro and run the plants on a starvation cycle later own in flower. The stored up saps and auxins reduce shock on the plant during the starve and allow it to resume growth more readily when you re-introduce nutrients. Blue lamps like Metal Halide, Murcury Vapor (mostly outdated) and fluorescents (argued to be too weak, but over-driving and foil-tape reflecting can fix that) can make for a more potent and more productive grow overall when given a long enough veg cycle to pay off, but recent technology has provided an interesting compriamise:
Ceramic Metal Halide bulbs are similar in construction to MH but use a ceramic core and the same ballasts as HPS. CMH bulbs have an extraordinarily white color balance, with even and high-powered output across the range. They have the best output ratings where it counts: PAR, as opposed to Lumens. A lumen rating is a decent comparison between bulbs for their brightness, but lumens are measured in the context of human vision. PAR is a measurement of brightness in terms of the light spectrum that is most efficient for photosynthesis. CMH bulbs will drive dense bushy veg cycles and nugtacular flowering finishes. CMH does have a catch, it can only be run by magnetic HPS ballasts, digital ballasts are incapable of running nearly all CMH bulbs. (there is an exception, too stoned to remember what brand it is, but they are pricey!) Despite its oddities, CMH is an amazing for cannabis, performing well in veg and flower. It even has advantages over HPS for flowering as its super-wide light spectrum means that it has significant ultraviolet output as well. UV radiation (ESPECIALLY UV-B) has a very positive effect on THC content of the flowers. Anyone who has ever treated cannabis plants with a lizard light (floro tube with 5-15% UV-B output) can attest to the way that new trichomes form and existing ones swell up amazingly! (Side Note: lizard lamps kick ass but they WILL cause damage to your plants if over-used. An hour or two a day in the second half of flower, when there are already plenty of trichs present to protect the buds, is pleanty with 32 watt %10 UV-b T8 florescent tubes)
It all depends on your budget really, CMH bulbs are pricier than bog standard HPS, but are priced competitively compared to horticultural HPS or MH. Some growers still swear by super-blue MH during veg and crazy-red HPS during flower, citing the sudden shift in color change throwing the plants into a frenzy. I don't have enough experience one way or the other, but I have witnessed some epic examples of both.
-DM
Hash Man
Member
I primarily veg under a mh, but for about 10-14 days i use an hps... i guess i should get some conversion bulbs, but ihave noticed some good growth, and my room gets so packed you cant even move around. i also limt stretch with lst, topping, etc.... which is a route to use. I guess you should use a mh if you can, but if you have an hps, realize that you may have to control the plant with training techniques...
JQP
Member
The benefits of running MH, or indeed any other bluer HID lamp, depend on what kind of schedule you're running. I've done low-head-room cytokinin-boosted ScrOG grows that only veged for 15 days. (thats starting from sprouted seeds taken straight out of the paper towels being stuck in the medium) In that sort of situation the benefit of running separate MH lamps would have far and away been outweighed by the massive added cost and complexity.
Indeed! MH gets you a bluer light temperature which makes for bushier, stockier plants. However, to some extent this condition can be replicated via supercropping: the practice of breaking the outer downward-traveling phloem section of the plants' main stems. From a 2-4 day old sprout you can take the main stem section between your fingers and gently squeeze while rotating it back end fowarth. You will feel the phloem give way and crush, there will be a little sound. The plant may lean over and bend a bit, especially on the first treatment, but when done correctly the plant props itself back up and gets a little thicker where you broke it. Wash, rinse, repeat! This eventually result is a massive stem cross-section and very short inter-nodal gaps. This completely halts the streaching of stem sections and it is totally possible to have a healthy plant with the fan leaf nodes closer than one inch to each other on the main stalk. The main stems go on to grow very thick and woody during flower, barking over on the wider sections even on very small plants. (like my earlier-mentioned 15-day-veg babies) You must be careful to only break the phloem; breaking the inner lines, the xylem, leads to catastrophic consequences. The xylem carries water and nutrients up from the root zone and crimping it off completely will kill all plant matter upstream from the break. Usually you won't break it off completely and the upstream growth will slow or stop while the break heals over. This stunted growth is not a deal-breaker, but it is not desirable either. The technique takes a bit of practice, but the resulting vigor and increased nutrient uptake is well worth it. This can be a way of making up for not using MH or floros or some other bluer lamp during veg, but it doesn't solve everything. Granted, I would recommend the technique even if you do use a blue lamp.
Bluer lamps for veg begin to make sense as you get into techniques involving fewer plants and longer vegatative cycles. The colder color temperature makes the plant run a slightly different chemistry that favors storing nutrients away instead of using them for massive growth. Larger fan leaves and stouter stems result and the vegging babies put away tons of sugars. This pays dividends during the flowering cycle, ESPECIALLY if you are running hydro and run the plants on a starvation cycle later own in flower. The stored up saps and auxins reduce shock on the plant during the starve and allow it to resume growth more readily when you re-introduce nutrients. Blue lamps like Metal Halide, Murcury Vapor (mostly outdated) and fluorescents (argued to be too weak, but over-driving and foil-tape reflecting can fix that) can make for a more potent and more productive grow overall when given a long enough veg cycle to pay off, but recent technology has provided an interesting compriamise:
Ceramic Metal Halide bulbs are similar in construction to MH but use a ceramic core and the same ballasts as HPS. CMH bulbs have an extraordinarily white color balance, with even and high-powered output across the range. They have the best output ratings where it counts: PAR, as opposed to Lumens. A lumen rating is a decent comparison between bulbs for their brightness, but lumens are measured in the context of human vision. PAR is a measurement of brightness in terms of the light spectrum that is most efficient for photosynthesis. CMH bulbs will drive dense bushy veg cycles and nugtacular flowering finishes. CMH does have a catch, it can only be run by magnetic HPS ballasts, digital ballasts are incapable of running nearly all CMH bulbs. (there is an exception, too stoned to remember what brand it is, but they are pricey!) Despite its oddities, CMH is an amazing for cannabis, performing well in veg and flower. It even has advantages over HPS for flowering as its super-wide light spectrum means that it has significant ultraviolet output as well. UV radiation (ESPECIALLY UV-B) has a very positive effect on THC content of the flowers. Anyone who has ever treated cannabis plants with a lizard light (floro tube with 5-15% UV-B output) can attest to the way that new trichomes form and existing ones swell up amazingly! (Side Note: lizard lamps kick ass but they WILL cause damage to your plants if over-used. An hour or two a day in the second half of flower, when there are already plenty of trichs present to protect the buds, is pleanty with 32 watt %10 UV-b T8 florescent tubes)
It all depends on your budget really, CMH bulbs are pricier than bog standard HPS, but are priced competitively compared to horticultural HPS or MH. Some growers still swear by super-blue MH during veg and crazy-red HPS during flower, citing the sudden shift in color change throwing the plants into a frenzy. I don't have enough experience one way or the other, but I have witnessed some epic examples of both.
-DM
I got some old 175W parking garage type HPS lights. Would they have a magnetic ballast? Yes, right? Could I use a CMH in them?
I'm only growing 4 plants. Today is Day 27. I have a 150W MH and 175W HPS, and rotate my plants every night. I will no doubt lose a couple of these plants to male, and then will flower the females with the HPS. I have to keep the HPS higher than the MH because of the heat the HPS puts out. That one HPS also makes a difference in my cold unheated rural NY cellar, pusing the temp over 80 in my little closet with no problem.
What I hope to do when I have more plants is use 1 HPS and 2 MH for veg, then 2 HPS and 1 MH for flower.
Let me know about that CMH would ya? Thanks!
JQ
First grow in decades: http://www.icmag.com/ic/showthread.php?t=113433
DrunkenMessiah
Member
The Philips Color Master line of CMH bulbs has a 150 watt product that runs near $30 online. I would be surprised if you could find a 175w CMH, the 150s are new enough themselves, for a long time it was only 400w and 1000w. Also, if you are growing from seed you might want to look into Bonide's Tomato Blossom and Set Spray. It is simply concentrated cytokinin; a natural growth hormone that has been found to drastically increase the ratio of females to males in single-sex plant populations, cannabis included! The original experiment is documented here:
http://www.plantphysiol.org/cgi/reprint/94/4/1535
Cytokinin foliar treatment is something that I think every seed grower should get into. I mix a 32 ounce bottle of tomato spray with one bottle of liquid ascophyllum nodosum kelp into one of those pump-action sprayers. Start them out on one treatment a week from 1 week old sprouts until you switch to 12/12, then go to twice weekly until 3 weeks before harvest where you halt treatment. It has done wonders for my cannabis as well as tomatoes!
while hps may not be the "best" for veging, it still excells at it. some clones, abit of lst and a couple of weeks of veg and you have a fucking bush and you cannot complain at that!
seed plants are stretchier and young plants risk burns and lots of stretching under hps, thats only bad thing, but even then you can, if you know what your doing and know your strain, easily control anything under hps.
seed plants are stretchier and young plants risk burns and lots of stretching under hps, thats only bad thing, but even then you can, if you know what your doing and know your strain, easily control anything under hps.
I used to veg under a hps but only cause i was growing autoflower plants in my veg closet. The 400 mh i have now blows my 600 hps out the water for veg. T5's are kinda garbage for real vegging in my opinion. They are only good to keep moms.
DrunkenMessiah
Member
*nods* it is difficult to beat the extremely blue color temperature of MH lamps during veg. They can be matched though, with the CMH bulbs I mentioned and you aught not to judge floros so harshly. Plugged into an ordinary shop lamp as they come they are pretty poor, but there are things that a good grower can do to bring them up to speed. Floro ballasts traditionally are wired up to a set of two tubes in paralel, but the ballasts are actually designed to run only a single tube if wired correctly. This practice is called overdriving, and its a hoot. You can read all about it here:
http://www.geocities.com/teeley2/overdrv1.html
Instead of running one ballast for every two bulbs you can modify a florescent rig to run one ballast for each bulb. The extreemly low cost of modern digital floro ballasts makes this very cost-effective. If you combine with this technique with foil tape reflectors you can get serious output from floros, they will generate some actual penetration and are capable of vegging plants from more than two inches away as growers are used to. Tape reflectors is simply the practice of applying foil tape (with CLEAR adhesive!) to the top half of the floro tube. Here are some detailed instructions on this process from the Overgrow.com Archives:
Can I use foil on my florescents?
Contributed by: Green Tao
In a shop light type fixture, the bulbs are usually space a few inches apart. This type of reflector creates light "stripes" when used close to the plants. The hood on a shop light helps to widen the light by reflecting the light coming from the top of the bulb. When you use this style reflector the light never leaves the top the bulb, instead its reflected back through the bulbs and sent out the front. If you doubt this works check with any aquarium shop and ask them.
The foil reflector: when you want the bulbs close to one another.
OK, all you need is a bulb and some 2" wide foil tape. Now, cut the tape so it is a couple of inches shorter than the bulb. This is for two reasons. First, the bulbs get hottest on the ends (heat can make the glue release and the ends of the tape will pull up). Second, it keeps the conductive foil away from the power at the end.
Before you start sticking the tape on, make SURE you have the bulb laying where the pins are horizontal to the floor. If your pins lock at an angle in the fixture, make appropriate compensations.
* Make sure you get the tape oriented with the correct florescent pin position when installed!*
Now start the tape about an inch from an end, and let the center on the tape stick to the very top the bulb. Keeping the tape straight, slowly run it down to the end. Tear off any excess at the end before sticking it past the last inch. Be sure to keep tension on the tape as you lay it - it helps to keeps the tape straight and centered (stops wrinkles).
Now that the center of the tape is stuck, start at the middle of the bulb and slowly make the tape touch a little more from the center out so that the tape is starting to take shape of the bulb. Work from the middle to end of the bulb. Don't try to get all the tape to stick in one try. The tape will not lift once set in place.
Note: trying to stretch a full length of foil tape and trying to lay it all-at-once onto the bulb is extremely difficult; if the tape touches anything it'll stick hard, and it tends to curl when you peel off the backing.
The results:
I took a comparison picture. The taped bulb is brighter and the light is focused downward. You still have some side lighting but as you can tell it is much less. The last picture is of a bulb that is over 30 days old and it shows no sign of phosphorous burning, stress or damage.
Using this technique you can literally create a wall of light. Floro's are not known for their power, so be sure to get all the light you can get out of them.
Editors Note: If your foil tape doesn't have clear adhesive, mylar can be used in it's place.
(*END*)
Sorry, my archive doesn't have any of the pictures in the origional, still looking for a good copy.... Anyway, don't be fooled, floros still remain a legitimate, low-cost option for vegging plants, it isnt just for rooting clones and maintaining moms. Good luck and happy gardening!
-DM
I just notice way bigger fans on plants under a mh compared to a fluoro. Like three times as big.
B
been
MHs are the bomb. I would suggest you do like IndianHay says and use it a few weeks into flower as well. My plants spend more time under blues than reds, and when you're growing indoors, you want short and tight plants.
I will check into CMH when they start making them in higher wattages, but right now my 1k MH is king.
I will check into CMH when they start making them in higher wattages, but right now my 1k MH is king.
Been using T5 for 3 years great results. You can only give your opinion and mine was very good and I still use them to this day. What does real veggin mean that's kind of a redundant statement don't ya think. Your plants are in veg or are in flower. Keeping a mother plants under T5 is good but veg is garbage that makes no sense IMO.
B
been
I also veg a tight plant with T5s.
DrunkenMessiah
Member
Yup! Un-moded floro tubes suck pretty hard! Good cannabis will grow veg matter relative to the avaliable light intensity and color temperature. Large quantities of very blue, very high penatration-rate light energy that you get from MH results in dense, bushy growth with big, dark, danky fan leaves bigger than your hand. The quantity of light and the blue color temperature make the plants go into a sugar-storing frenzy. The massive fan leaves and thick woody stems are its way up upping available storage space. This in turn can result in massive buds if you switch to a redder light later on, with all of the stored energy being poured into the flowers. Typical floro tubes on the other hand seem to hold up a measly candle in the face of all that performance. It seems they are only any good for sprouting and rooting clones.
However, I'm just saying that isn't a reason to count floro technology out as a viable and very cost-effective method of doing lots of useful things. Overdriven floros only cost five bucks more per pair and coupled with foil tape reflectors will make some bright motherfuckin lights. I would dare you to stare unblinking into an overdriven, foil-taped 48 inch T8 tube! They are hilariously bright and easily tuned to a lovely, specifically blue chunk of the light spectrum. They will do an outstanding job of vegging plants for up to 4 weeks. If you want to make some monstrous plants and veg for more than a month then MH is sortof the only way to go. Also, in my early days I ran a few organic soil ScrOG grows to complete fruition lit by nothing but 4 48" T12 floros prepared in this way. Thats four two-bulb digital ballasts wired in series into a single bulb instead of two bulbs in parallel. This results in a real-world 70% increase in light output from each tube, due to heat loss and other thermodynamic bugbears, giving me the brightness of 6.8 normally driven floro tubes in the space of 4. This sounds pretty good, but doesn't prepare you for seeing one in action, they are crazy-bright. Vegetative matter up to 18 inches away gets usable light (if using the foil tape) and there is actual penetrating power reminiscent of small HID lamps (like 150 watt MH). I personally vegged with soft blue tubes and then swapped in some wicked 2900K color temperature aquarium T12s for flower. The resulting buds didn't have the density of big HID bud but because of the flat ScrOG setup they where all mere inches from the nearest light. It was extreemly potent and smooth-toking due to a nearly all-organic (cheated and used Bloom Burst at 2 teaspoons per gallon of water a few times during flower, couldn't resist
) nutrient regime.I've since moved on to bigger and better things. Cost-effective as floros can be in this modded-up form they still don't match the 400 watt and up HID heavyweights for efficiency, output, etc. However, having stuck with 400 watt HPS and CMH for some time, I did still find a use for floros even in flower. If you ever get a look at a set of regular overdriven floros in action and think that they're cool, you should see a an overdriven pair of these:
http://www.drsfostersmith.com/product/prod_display.cfm?c=6016+6028+19108+7892&pcatid=7892
Actually, you shouldn't see them, or at least not directly without eye protection! (you need at least some nice UVB-rated shades like this dude:
) I ran a 6 inch diameter PVC cooltube with a single 400 watt HPS over a 3x3 foot concave ScrOG. I found that it was easy to 'fly' a pair of overdriven and foil-taped 36 inch Repti-Glo 10.0 tubes off of the cool tube like such:
(note: image is a cross-section, the black circle around the HPS bulb is a cool tube, the lights are not spherical)
Because of the frightening output of the overdriven 10% UVB bulbs (in overdriven form the bulbs are generating five watts of pure UV-B energy EACH, and UV-A output is in excess of fifteen watts!!!) they had to run on their own digital timer so that I could get them to run for only 30 minute stints through the middle of the 12-hour 'day' for a total of 150 minutes a day and the treatment can only start once the plants have already developed a decent layer of trichomes to protect the flowers. Much more than this causes burning in the form of rapid necropothy. Done correctly though and the existing trichs swell massively and new ones grow between the preexisting ones. THC content by mass goes through the roof! The buds become covered in what can only be described as a thick hashy layer of trichs. Burn a bowl packed from one of these nugs and you'll never dismiss floro technology again!
Good luck and happy gardening!
-DM
S
sparkjumper
I've heard a lot about plants stretching noticibly more under the same wattage HPS as opposed to MH.I run a sun systems 800 watt combo HPS/MH and I see no difference at all really.I'll use the MH to veg sometimes,sometimes the HPS because I was interested myself.I switch them both on when they get big enough.But in my experience I've see no real difference in plant growth between the tw
ne thing I can tell you,the 400HPS burns a lot brighter than the 400MH.It may not be the perfect spectrum for veg but it puts out more light without question.It quite a visable difference
ne thing I can tell you,the 400HPS burns a lot brighter than the 400MH.It may not be the perfect spectrum for veg but it puts out more light without question.It quite a visable difference
M
moses224
there should be not debate. i have tryed 250 to 1000w hps the plants STRETCH
you are better off with a high watt cfl then hps....but now a days ballast are so cheap just go diggy mh and use hps for flower assuming your grows small eough
N
nesvarbus
But hps puts out a eyed light more than mh with more blue specter !!! This is defferent things
I've heard a lot about plants stretching noticibly more under the same wattage HPS as opposed to MH.I run a sun systems 800 watt combo HPS/MH and I see no difference at all really.I'll use the MH to veg sometimes,sometimes the HPS because I was interested myself.I switch them both on when they get big enough.But in my experience I've see no real difference in plant growth between the tw
I agree! Folks can say what they want, but after years of fuckin around with all the different wattages of MH an HPS, I found the HPS will veg plants just as good as MH. With no extra stretch. They even grow faster with HPS. Plus ya get 30% more bang for the buck!
BC
