Vegging 24 hours, and wattage/electrical cost vs speed

[malachii]

Hi guys,

At the moment I'm growing with a 400w HPS. In the past I used this just for flowering (t5's for veg). Now I'll be using the HPS for both.

So my question is - now that the light will be on 24 hours a day for veg, I was considering changing to a dimmable ballast to go 250w for veg (to cut electrical costs and noise in veg).

I wonder if those 150 extra watts (at 400w) would grow the plant 60% faster than a light at 250w, such that in the end, I would consume the same amount of total power? Which way do you think the balance swings?

Thanks!

Mal.

 

[Bluenote]

Some idea of the square footage for veg would help , and what were you running for T5s?

Personally I only run the 400s for veg in specific cases , it helps to harden off certain of the strains I have and it definitely helps with an ultra-slow veg strain like Urkle. But the vast majority of my veg nowadays is with T5s and to a lesser extent T8s in the mix in one large space that maintains my mothers.

Kind of a hard question to answer , if you're on a tiered rate structure you'll likely not like the results from a cost versus return standpoint. You may wish to consider 18/6 by the way , might end up being a decent compromise , about the only thing I run 24 on anymore is clones and they go to 18/6 a few days after roots show and prior to transplant.

YMMV on all this , as I stated it's kind of hard to answer it from the available info.

 

[malachii]

Ok, a little more information is needed I see. I'm growing in a very limited space - my small 3x2 closet.

Yes - I am on a damn tiered electricity setup based on time-of-day (with crazy rates during the day).

I have a tiny space available on the bottom part of my closet with 2x24w T5s (2') that I use for cloning, and 'initial' vegging to save a couple of weeks. It's very low, and is mostly to house my res.

I used to have a separate closet for vegging - but I no longer have access to it. That's where I had T5's before.

I find it to be a giant pain to put T5's (4x2' @ 100w total) in my primary grow area just for veg, then change it all over (ducting changes, etc) for my cooltube setup (it's a scrog)

So really, my options are:

1. use my 400w hps for everything, vegging at 24h.
2. use my 400w hps for everything, vegging at 18h (saves a little coin, but does it not slow the growth, resulting in similar total watts consumed? no experience there).
3. buy a dimmable ballast, and veg at 250w, 24h.
4. buy a dimmable ballast, and veg at 250w, 18h.
5. buy a dimmable ballast, and veg at both 250w and 400w depending on time of day, but I'll have to manually change it twice a day.

* note: I would likely buy a hood instead of a tube for the new ballast so I could more easily change to an MH bulb if that helps any.

So which setup yields the best growth/total watts consumed? That's really the question.

Thanks!

 

[Bluenote]

Option #4 is quite likely going to be your best one , no point really to running 400 watts for veg in that small of a space.

The whole 18/6 versus 24 thing is the subject of a great deal of debate , I am of the opinion that I get somewhat better results 18/6 , and it *is* less expensive.

When you buy that ballast? Might as well get one that goes 600/400/250 , it won't cost you any more and you'll set yourself up for future minor expansion.

If you get a switchable ballast i.e. MH/HPS cpable you could run a 250 MH for veg a a good ( LucaLox or Hortilux Eye etc...) 400 HPS for flower. That's quite likely to be the most advantageous from a cost versus return standpoint on the power factor. It will also save you some money over the longterm on HPS bulbs as you'll only be running them on 12/12.

 

[El Cerebro]

I'd go MH during veg for sure. If its an HPS ballast just grab a conversion bulb (online, not 2-3x hydrostore markup). Way better spectrum for vegging than any hps, healthier plants with a lot less stretching . Ceramic Metal Halide is a great option too, and they work with a 400w magnetic hps ballast. With CMH you'll get better veg spectrum and higher flower/trich quality than the hps alone if you're using just one bulb for both cycles (a lot of us mix hps and mh for this reason, 1mh to 2hps is typical, or some just add/switch to mh the last few weeks).

I also think with limited space and just one light, why not stick with 400w in veg and get that much more budsite development before flip? The difference in outcome should far outweigh additional electricity cost. The 400w mh would make a fine veg lamp, then swap to hps for flowering, then back to mh at the end. No additional cost beyond the second bulb, then they both end up getting half as much action (last twice as long).

Giving the plants a rest in veg is good, have mine on 20/4, except for clones taken in flower are on 24/0. Apparently certain strains can be sensitive too, no experience on that though.

 

[paulycali]

Veg with the MH and then switch out the bulb to HPS when ready to flower. Best way to go for sure. I used to veg under hps. Its alright. I would only do it if youur going to veg for a few days or so. Then its all good. At least get a switchable ballast so you can run your veg watts lower and flowering watts higher. Good luck with everything

I veg 24/0 as well. Plants take off for sure. I veg on 600W MH and flower at 1000W HPS

 

[malachii]

I'd go MH during veg for sure. If its an HPS ballast just grab a conversion bulb (online, not 2-3x hydrostore markup). Way better spectrum for vegging than any hps, healthier plants with a lot less stretching .

Yes, I will be going MH - the replies have been consistent on this.

I also think with limited space and just one light, why not stick with 400w in veg and get that much more budsite development before flip? The difference in outcome should far outweigh additional electricity cost. The 400w mh would make a fine veg lamp, then swap to hps for flowering, then back to mh at the end. No additional cost beyond the second bulb, then they both end up getting half as much action (last twice as long).

I think you might missed my concern about electrical costs during the daytime where I'm from.

I don't have time to make detailed calculations, but my high daytime rates (12 hours) are 60% higher than my nighttime rates. I want to reduce my consumption, especially during those hours.

If I veg at 250 instead of 400 (in my 2x3 foot space) I'm consuming 60% more power, for now let's say 24 hours a day. Will I get 60% faster veg growth at 400 watts to make it worthwhile for me (saving veg time is good). I'm not sure what difference to expect during veg between the two (using MH). I'm guessing the growth rate would be somewhere in between 0% and 60% faster, let's say 30% faster. Somebody else may have experience with this.

Giving the plants a rest in veg is good, have mine on 20/4, except for clones taken in flower are on 24/0. Apparently certain strains can be sensitive too, no experience on that though.

I believe another reply suggested 16/8 for me, which may make sense because I can avoid the high daytime rates for those 8 hours. Vegging for 24 hours instead of 16 uses 50% more light electricity. Will I get 50% faster growth using 24h instead of 16h? If not, it's likely not worth the tradeoff.

 

[El Cerebro]

Yeah you can save a lot by running lights at night for sure, about 60% where I live too, winter and summer peak times usually vary. Thing is, with just one light I would think the extra yield will easily pay for itself on the first harvest. Seems like a lot of us tend to be so frugal, even when it only means saving a few $, and that extra cost is effectively irrelevant unless your running something big.

18/6 will do fine, just a little slower veg. I've heard a lot of people claim 24/0 is actually slower than when plants are given a rest, so just a matter of deciding what works for your situation. I'm not sure about the growth rate %s, but I know the 400w will give considerably better 'penetration' distance with more radiant energy over the same area (plus you already have the ballast?) You can get decent 400w mh bulbs for $19 online and not much more in a lot of hardware stores.

 

[Bigcorners]

I currently also use T5s for all my vegging needs, while on a recent trip to Amsterdam i learned about Plasma lighting and its benefits and disadvantages. First of all i was iffy, never heard of it and it sounded like fluke, but in actuality its awesome! Kinda like when LEDs first hit the market, no one knew anything about them and now there the next step in lighting supposedly... So my mind when i was thinking of going MH,i defiantly decided to be getting some LEP instead.

So a LEP is a Light emitting plasma a tiny tiny tic tac sized bulb literary, it has a 30K hour run life! the light output is staggering, like a LED lights that have different spectrum leds all together. the LEP has every single spectrum unlike HPS that only have prominently red and yellow spectrum output the plasma puts out blue,green, yellow, red giving the plants more of what they need and not what we perceive they need get me? cause we as humans can only see certain spectrum's and we have always thought HPS and MH were perfect, but plants see all spectrum's and can benefit from almost all spectrum's including blue, and green which are almost unseen in most "common" current lighting, along with UV-B which the plasma emits as well. The bulb runs cool, and is almost heartless, you can touch the lamp, surrounding and glass and they are warm at the most. The glass filter also filters off bad UV-A but lets the beneficial UV-B get to the crop. If you ever have a problem with PM the UV-B kills it instantly so no more PM problems at all, if you have them. This light is a monster as a VEG only light and adds amazing results along side a HPS in VEG. a couple growers who i chatted with commented to say it the addition of 1 to 4 LEP lights to there current system say results comparable of a crop run with CO2 vs a crop run without C02 somewhere from 15-30% boost in growth, node sites, and overall weight.

Defiantly something im going to invest in a couple months. Sorry if i didnt have anything to add to MH debate, but its worth a look if you want some of the best :) its amazing!