Help with MH & HPS

Discussion in 'Growing Marijuana Indoors' started by TooSober, Jun 1, 2009.

  1. I've been looking on eBay, and have found some reasonably priced 400 watt HPS/MH systems for 100-200 bucks. That sounds like something I can do, but I'm seeing stuff I'm not familiar with. My original plan was to use all CFL's, but if I can spend $200, and get MUCH better lighting, it only makes sense.

    So, tell me what I'm looking at! I see electric, digital, and magnetic... Huh? Is one supposed to be BETTER? and why?

    I'm also seeing a huge difference in lumens with 400 watt bulbs.
    Why are some like 50,000 lumens, and some like 80,000?? Is the difference that much more noticeable? My box is only 2.5' x 3' x 4'.

    Help me out here before I go wasting money on something I'm not sure about.

    Thanks a lot in advance!
  2. I got my 400W HPS/MH switchable ballast with 2 bulbs and a sealed air cooled reflector for $130 off of Craigslist. It's always a good idea to try and pick up the item yourself than have it shipped to you.

    Magnetic ballasts are the standard. Digital ballasts are more energy efficient, but I've heard they break a lot, which makes sense.

    I've heard more expensive bulbs aren't really worth the extra money, but that's only what I've heard.

    How are you going to do your ventilation? I think that's the first thing you may want to think about. If you need an example, here's my setup...

    Hope this helps :)
  3. one of the eBay stores is actually really close to me, so if I decide to go with the MH/HPS system, I can just run over there. As far as ventilation, I just have a four inch cooling fan on one side, and a four inch exhaust fan in the center of the top. The box is also indoors, so I don't think temp will be an issue. Do MH lights produce a lot more heat?
  4. A lot more heat than CFLs, that's for sure. In that small of a space, you're going to need ducting and an air-cooled reflector, or you'll never get your heat problem under control.

    That or stick with CFLs...
  5. Yea air cooled - glass enclosed reflectors make all the difference.
  6. watch out if area is a bit small. mh/hps bulbs will heat up it significantly:eek:
  7. Magnetic vs. digital is referring to the ballast, which you must use with HID lighting. In simple terms, the ballast regulates the electric flow to the bulb. A HPS ballast also has an igniter, which HPS needs. FYI, fluoros need ballasts too. CFLs have them built in.

    Magnetic is the old technology -- it is cheaper but it buzzes more loudly and generally is made for only HPS or only MH. You can still use one magnetic ballast by getting one (for example HPS) and then for the other type of bulb get a "conversion" bulb, which is made to run off the other type of ballast (for example, MH conversion bulb made to run off a HPS ballast). Keep in mind that conversion bulbs are more expensive, so if you are thinking of a magnetic ballast as a way to save money and you want to use a MH bulb for veg and a HPS bulb for flower, in the long run the higher cost of the replacement bulbs, with one being a conversion bulb, may not save you anything. There also are switchable magnetic ballasts, which essentially brings the igniter online or offline depending on the bulb you are using. For those you don't need conversion bulbs.

    Digital is the newer technology, it's quieter and can run either MH or HPS no problem. It costs a bit more and is supposed to be more dependable.

    Be sure that whatever kind of ballast you get, it is not attached directly to the socket or hood. Ballasts give off heat, so you want to be able to keep the ballast outside of your grow space.
  8. WOW! Thanks a lot for the info.. just about covered everything i wanted to know..

    Unfortunately, I now realize I will be sticking to CFL's.. :(
    I really wanted to get a HID set up, but I see now, I will need one of the more expensive digital set ups, with the glass covered reflector and air cooled bulbs... a bit more $$$ than I had anticipated.. maybe once i get a few crops under my belt, and possibly a lil income from them, I can get a nicer light set up.

    I feel confident, with the size of my box, CFL's will be OK... for now at least.. still makes me kinda sad though.


    Wish me luck, as my seeds haven't even SPROUTED yet.
  9. Yeah, a HPS system is the way to go, but good things can be done with CFLs too. I use CFLs and one T-5 unit in my box, which is 4'x4'x6', and I still manage to pull off some respectable yields. Check out Kamel's CFL thread at the beginning of this section, it will give you the whole rundown on CFLs. Also feel free to PM me with any CFL questions, I'm happy to share my experiences thus far.;)

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