Swapping between HPS and MH bulbs

[ChilliUK]

Hey there guys,

From reading up on forums and websites over the years about the pros and cons of HPS vs MH bulbs and how a grow with mixed lighting can offer the benefits of each type of bulb when combined together in a growroom got me thinking.

My grow is only a small 400w hps setup and my space only 6 sq ft approx, so fitting any more lighting in there would be impractical and intensity wise a bit of a waste.

However my ballast will rn both HPS and MH bulbs so it got me thinking about maybes buying a MH bulband swapping the two types out say every few days or maybes once a week during flowering. So for example on weeks 1,3,5,7,9 i could run the HPS then on weeks 2,4,6,8 I would change to the MH bulb.

Have any of you tried something similar and if so did you see any differences, improvements in quality etc. The only thing that kinda put me off trying was I thought maybes the drastic change in colour temperatures between the two bulbs could somehow stress the plant in flowering somehow??

be great to hear other peoples thoughts on this.

peace

chilli

 

[CHILKaT]

I don't know, switching back and forth between the two might cause more harm than good. I haven't done it, so I can't say what the outcome would be.

I use both HPS and MH and a few CFLs, together. For a smaller space, I would recommend you add a couple of CFLs. These are perfect for supplemental lighting. CFLs offer the broadest light spectrum of any class. When equipped with a premium tri-phosphor coating that broadens the light emission even further, CFLs produce an almost flat spectral "curve" that can be designed to compensate for specific spectral deficiencies of the high-lumen HPS bulbs of most successful high-yield gardens. Supplementing HPS lighting is something I do recommend as it did increase yield.

 

[hubcap]

i havent tried that method either for two reasons:

1) seems like a PITA (pain in the arse) and i'm a BIG believer in the KISS (keep is simple, stupid) methodology.
2) one can garner great results running MH all the way thru. Likewise with the HPS.

alot of people, myself included, either run MH during the whole veg cycle and switch over to HPS during flower.
on the other hand, ive also been known to run MHs all the way thru, as well, and get great results. if i had to pick one bulb or the other....id pick a nice MH.

switching bulbs every other day seems like a pain and ups your odds of bad things happening.

i wouldnt bother.
but some other farmers might chime in.


-cap

 

[AlienBoyD7]

I have had success using Mercury Vapor and HPS rotating the plants around the room.

 

[ChilliUK]

Thanks for the replies fellas,

I dont really see it being a pain to do, I mean it doesnt take long to screw one bulb out and the other in once a week, but maybes it wouldnt really be worth it. I just thought it could be a nice way of exposing the plants to the differing spectrums of the two bulbs without having to run two lights at the same time.

Chilli

 

[dooobster]

You could get a couple of T5 or T8 fixtures and mount them on the walls in your grow space, daylight spectrum fluorescents offer a lot of blue spectrum light that should give you a good light mix in there...

 

[aphid]

If you are only running a 400 why don't you buy a CMH(ceramic metal halide) bulb and run it the whole grow. It's got what you need for veg. and flower all in one and can be picked up for about $50.00.

 

[aphid]

P.S.- It runs off a hps ballast.