400w HPS vs MH veg

I've been trying to figure out what would be a better way to go while vegging for my 3rd grow.. 400w HPS or 400w mH or turn down to 50% and use 250w MH bulb? I'm really restricted height wise, so I'm trying to mainline and use multiple scrog screens about 6in away from each other to help support multiple colas. My tent is 2x4x5, container about 11in (14 gallon tote) light/fan/filter combo taking up about another 19in. I can't seem to find a solid answer on which light would be better for shorter plants, I think the HPS would be better because the spacing between nodes should be shorter. But I think it really comes down to the bulb, so I've been looking at Eye Hortilux bulbs which are about 10x the cost of the bulb I'm using now.. but it seems to cover a better 'spectrum' - worth it to you guys?

Another question that popped up is should I even be bothering with the 400w in a 2x4 area and scrog screens 24in x 18in? Can I actually get fatter buds or anything?
Should I just get a 250w and use the ballast at 50%? Would that even work?

Hey I would go 250 mh then flower with 400. on my phone now will go into more when I get back.
Moondance

Okay Hi how are you? Bulbs yeah it's a preference thing, some are better than others and you pay for it. Im the long run though the better bulbs will last longer without loosing to much power over time. For example I run a ushio opti red 600 for flower bare bulb, but for veg I use a 250MH, sometimes I through in the HPS bulb in veg. If it were me I would put the HPS in and veg to fill the screens when your happy flip it keep tucking for 2 weeks and bud it out. Scrog allows the most bud site to pop up through the screen, so maybe more yeild, but each cola gets their proper light. Same with running vertically like I do, each bud site get the most possible light. I run the 600 in a 4x5 space, I think you can make the 400 work, watch your temps get plenty of fresh air in and heat out. Yes you can dim the ballasts down if they have that function, I do it all the time run my 600 at 400 or 350. It comes down to your decisions though. Hope it helps.
Moondance

When he says 400 he means 400w hps

Hey Weishen,

MH has a more desirable spectrum of light for plants in the veg stage. If you want light nodes it is dependent on your strain and your light distance. (Mostly strain but far lights make plants stretch)


My current grow is in a 2x2x4 tent. I am growing a Scrog in a 5 gallon bucket with a 400w MH veg and now HPS for flower.

I turned down my ballast to 50% for veg. 100% for flower.

As long as you get an air cooled hood you should be fine with a 400w MH turned down to 50%. And you don't need an extra 250w bulb. The 400w will just dim.

Check out my grow for more details and tons of pics.

https://www.rollitup.org/t/my-400w-mh-hps-super-skunk-grow.919144/

cannabisweedPotNerd said:

When he says 400 he means 400w hps

Click to expand...

Yeah I know what he meant Thanks
Moondance

Run the MH until stretch is over then switch to HPS. Plants build a lot of new material and the bluer spectrum of the MH aids in that and keeps light levels high so the plants don't "stretch" so much. I've noticed greatly reduced stretch doing that.

I think the high end bulbs are worth the money. I'm vegging plants under a 15 yo EYE now and they like it fine. It's a conversion bulb that gives me MH light off of an HPS ballast and cost $130 15 years ago. Just bought another one to give me flowering light off of my 1000W MH ballast in August and it was $170. If I get 5 years off of it I'll be a happy camper.

I also have another $100 400W EYE Super hps that runs off an hps ballast and it seems to work better than the $60 SolarMax. Just bought a couple of cheaper PlantMax MH bulbs for vegging. A 400 and a 1000W, $40 and $60 respectively.

I've tried growing with the standard MH and HPS bulbs but the results were very disappointing tho I still read posts where they are seen to be as good as ones that have plant-specific spectrums. I say BS to that.

ScroG is great to control the canopy and to support phat colas. Just putting a screen up to support buds does not make a ScroG tho. Tying the branches down as they grow horizontally until the screen is almost full before flowering is a real ScroG and one of my favorite ways to grow. DWC ScroG is killer!

Everything I've read about dimming your ballast drastically reduces the life of your bulbs unless you use the bulb size that matches the dimmed setting. All my ballasts are 20 yo magnetics and rarely does a bulb fail in any of them. They don't send digital fingerprints to your power company thru a smart meter either which we don't have here in Alberta.

Hi guys, great info thank you so much.

I will definitely start using mH during veg then, I really need short as possible plants in this small area.

My scrog design has not really been working that well because I have not been trimming or cutting much off.. just worried but now that I've read some mainlining and supercropping articles, I am going to go for it. The 2nd and 3rd scrog screen is just gonna be an add-on because in my previous grows the branches keep falling to the sides, really weird stuff going on etc. but if I do it right this time, I'm pretty sure I won't even be using 2nd and 3rd screen. I was feeding the plant through the holes, trying to go over and into other branches, tying down, etc but it just wasn't working right... I only had 1 main cola the entire time.. that was kinda of looping around the screen. So mainlining and TOPPING make a LOT of sense to me now..

One thing I'm still a little confused about is quality of the bulb. I've read that bulbs should be replaced every year or 2-3 grows because lumens drop. But OldMedUser is saying he has been using his for 15+ years with no problems. Looking at my results with my standard 6$ hps 11$ mh bulbs from Apollo, I kind of agree that they are disappointing.. the buds do not get that fat at all, maybe like 2in at most lol. Any other insight on cheap vs quality bulbs? Will I actually have to be replacing it that soon?

The super hortilux eye hps is on amazon for 60 but having a bit of a hard time figuring out which mH to get. First - 250w or 400w if I'm going to be dimming to 50% - will that actually be 200w?
And the current mH I have is similar to the HPS, just slightly fatter but the ones on amazon are all really round fat types.. like a melon in the middle round.. are those for special ballasts? Here is what I'm working with: https://www.amazon.com/Apollo-Horticulture-GLK400LS24-Digital-Dimmable/dp/B005ECY4UQ

OK what about the 400w mh conversion bulb from solar max I'm buying one today there expensive 100 and something dollars but they must be quality bulbs for that price I run a 600w hps one in my flower room and seems to be better then the other one I'm using but yeah a mate told me to go with this brand

Weishen1121 said:

OldMedUser is saying he has been using his for 15+ years with no problems. Looking at my results with my standard 6$ hps 11$ mh bulbs from Apollo, I kind of agree that they are disappointing.. the buds do not get that fat at all, maybe like 2in at most lol. Any other insight on cheap vs quality bulbs? Will I actually have to be replacing it that soon?

Click to expand...

I'm saying the bulb is still usable after that long but how far from spec it is I have no idea. A lot of guys get new bulbs every couple grows because they think it will make a big difference to yields but think about it. If the performance drops 15% after a year of 18hrs/day then running it 15% closer to the plants should make up for that. As long as the plants are happy so am I and a thicker wallet feels good too.

I've tried using cheapo bulbs and the plants tell teh storry there. Never looked happy when I ran a PlantMax 400 but perked right up when I got my HPS ballast fixed and swapped in the Hortilux conversion bulb.

Talking about fat bulbs check this one out. The one on the left is a the standard size 400w hort conversion and the one on the right is the Hort 940W conversion bulb that gives HPS light off the 1000w MH magnetic ballast. That's an 18" ruler there too. f'n thing is like a football and sells for $300 now. I paid $170 for that one 7 years or so ago and only used it for one flowering cycle so far. Don't often need 1000w to do the job.

Sam sneak said:

OK what about the 400w mh conversion bulb from solar max I'm buying one today there expensive 100 and something dollars but they must be quality bulbs for that price I run a 600w hps one in my flower room and seems to be better then the other one I'm using but yeah a mate told me to go with this brand

Click to expand...

I've always put SolarMax in the middle of the road but a lot better than PlantMax. If you have a 400w HPS digital or mag you should hunt around for a GE ceramic metal halide, (CMH), bulb. I'm running a Philips atm off my old HPS ballast but they don't make those any more. Sometimes checking with a regular electrical supply store can find bulbs like that cheaper as they aren't sold as special grow lights. I should have got a 6 pack of Philips 10 years ago but didn't have $300 to spare at the time. $50 each was a great price with 400W hort bulbs going for over $100.

OldMedUser said:

I'm saying the bulb is still usable after that long but how far from spec it is I have no idea. A lot of guys get new bulbs every couple grows because they think it will make a big difference to yields but think about it. If the performance drops 15% after a year of 18hrs/day then running it 15% closer to the plants should make up for that. As long as the plants are happy so am I and a thicker wallet feels good too.

I've tried using cheapo bulbs and the plants tell teh storry there. Never looked happy when I ran a PlantMax 400 but perked right up when I got my HPS ballast fixed and swapped in the Hortilux conversion bulb.

Talking about fat bulbs check this one out. The one on the left is a the standard size 400w hort conversion and the one on the right is the Hort 940W conversion bulb that gives HPS light off the 1000w MH magnetic ballast. That's an 18" ruler there too. f'n thing is like a football and sells for $300 now. I paid $170 for that one 7 years or so ago and only used it for one flowering cycle so far. Don't often need 1000w to do the job.

View attachment 5091226



I've always put SolarMax in the middle of the road but a lot better than PlantMax. If you have a 400w HPS digital or mag you should hunt around for a GE ceramic metal halide, (CMH), bulb. I'm running a Philips atm off my old HPS ballast but they don't make those any more. Sometimes checking with a regular electrical supply store can find bulbs like that cheaper as they aren't sold as special grow lights. I should have got a 6 pack of Philips 10 years ago but didn't have $300 to spare at the time. $50 each was a great price with 400W hort bulbs going for over $100.

Click to expand...

What bulb would be the best you think 600w hps

Sam sneak said:

What bulb would be the best you think 600w hps

Click to expand...

I use Hortilux Super HPS in my 600s and everything else. They are the only digital ballasts I own. Have 3 of those, 3-400W HPS, 1-400W MH, 1-1000W MH (dead), and a 1000W MH/HPS (working with new capacitor). Only have one small 200W from the wall COB LED and a DIY LED that uses 11-9W 5000L light bulbs with the globes popped off.



Have built up a collection of bulbs over the years and rarely use more than two at a time but like having spares of everything.