I have a 1k watt m.h not being used. I had a m.h to h.p.s conversion bulb and was using it for flowering. the bulb blew and I cant drop $200 on a new one right now. I was thinking, since I am flowering with 1-400 m.h and 2-250 hps spread out over a5x7 area in the flower room, which is not enough. should I replace the 400mh with the 1000mh? I know if you don't have enough light you get stretch and low yields,. from what I understand flowering with m.h causes stretching. would putting the 1k in there help with the yield side of my issue?
The MH won't really cause significant stretch during flowering. It just has a more blue spectrum and is better suited for the vegetative growth rather than the flowering process. That being said if you have a 1k watt MH or a 400 watt MH to choose from I would definitely use the 1k watt. The penetration will be a lot better with the 1k watt as apposed to the 400. You'll get better yields with the 1k watt MH than with the combo of low wattage lights you're running now. I flowered my Autos under a 1k watt MH and got good yields and great ganja from it. If you have a choice between MH and HPS then choose the HPS for flowering but if it's just a choice of higher or lower wattage then choose the higher wattage.
"I have a 1k watt m.h not being used. I had a m.h to h.p.s conversion bulb and was using it for flowering. the bulb blew and I cant drop $200 on a new one right now. I was thinking, since I am flowering with 1-400 m.h and 2-250 hps spread out over a5x7 area in the flower room, which is not enough. should I replace the 400mh with the 1000mh? I know if you don't have enough light you get stretch and low yields,. from what I understand flowering with m.h causes stretching. would putting the 1k in there help with the yield side of my issue?" So, first things first. The lighting FAQ section has a lot on this so if I miss something it'll be in there. Plants use light from a MH 2-3 times less efficiently in flowering if I remember right. That frequently only affects yield though and you end up with more resinous buds since there is a higher UVB spectrum in metal halides. The blue spectrum also limits stretch significantly, which is why combined MH/HPS lighting for the first couple/few weeks of flowering is common. I believe there are a few CMH 400w grows you can look up for a more in depth discussion on the topic. As far as switching the light, that depends on if you can manage the heat and intensity. The plants will do better if you have a way to hang the MH separately. If not, you probably will have a hard time not roasting your plants in some way, since the 2 250s need less than half the distance to the plants and probably 1/4 of the cooling (it always seems to me like MHs ran hotter). if that's a bit long.
Mr. Stynky, the 1k is in a dome type sealed hood, I hung it up about 3 feet above, in the middle of the plants and left the 2-250w hps hanging 1 foot above them on either side of it. I finally got my heat issues handled last year, so I'm not too concerned about that.( man that's nice to say). anyways the switch has been made. I think more watts is the right choice. i'm still not sure about $200 on a 1k conv. bulb or $300 on a 1k hps ballast set up. that decision will be made in a couple more months standing at the counter in the grow shop. I thought about getting a 400 conv bulb, but they were out at the time. I have 3 400 and 1 250 metal halide ballast I got off the job for free. the 1k cost me $60 or I would have 3 or 4 of those.
