so i scored last night! a friend of a friend had a 250w MH to HPS conversion system (ballast, reflector, MH bulb, HPS conv bulb.. everything). so it's now mine. it's three years old and was in storage for the last two. the bulbs are in good shape. so my question is that i'm 5, almost 6 weeks into flowering with all tubes and cfl's, and i wanted to know if switching to hps now will fuck anything up, or will it just increase my yield? i know there was a thread on this forum that said for what wattage hid light how far from tops of plants? the guy who gave this sytem to me said to have the MH bulb about 6 inches away, and the hps a cunthair further. anyone know? i sure don't. and on the box it says this system will accomodate a 3' by 3' plot (around three short but bushy plants) does this sound right? any tips/hints anyone has on MH/HPS conversions please let me know. also i've seen on ebay HPS to MH conversions, but not MH to HPS. are those 'old news"? i understand that i can use any 250w MH bulb, but i have to get a MH to HPS bulb for HPS? that right? sorry for the novel, any help is appreciated.
Hey man, I have a 250watt HPS and would think that you'd be fine bring the light in this late. I don't think it's powerful enough that it would shock your plants or anything with the huge increase in lumens. As far as the distance goes, it all depends on circulation. The more air you have moving near the bulb, the cooler it will be below it, so you can lower them more. I just looked at mine and I would say it's about 6-7 inches from the top. Also, I think about 4 big plants, in LST, should be the right size for the light. That's what I'm aiming for with my next grow at least. Hope that helped you out some.
with the reflector hanging about 4' above the floor, the light coverage is only maybe 2 1/2 feet x 2 1/2 feet. does anyone know a website that sells just the reflector? a bigger reflector will give me more coverage, but less intensity, correct?
so today was my first "full" day with the 250w hps. i got home from work about an hour ago (4:30pm) and i find the tops of all my plants leaves were turning/curling up. picture the leafs as your hand (palm up) and make a 1/2 fist. i wonder if this is due to too high room temp or the light too close?? the guy i got the light from, and kayakbubbler said that 6 or 7 inches from the tops of the plants should be ok. so this leaves me to believe that it is room temp (boy these hid's put out some heat!!) causing this, but but but, if it was room temp wouldn't all of the leaves have this problem?
6-7 inches should be fine. At the end of my last grow my 400 hps was a few (3 inches) from the tops with no problems. What is the temp in the room and do you have at least a 4 inch fan blowing at the light/plants?
i'd say temp in the room is high 70's to mid 80's. six inch clamp fan blowing at the bulb/tops of plants. any ideas on the leaves curling?
You know what? Now that I think of it, it is a good idea to introduce the light to them slowly. Have them a bit further away and give them only a few hours of hps light at first. They need to get used it it a bit. Seedlings need to get used to it a bit more but, adults can be shocked. ids the curling at the tops of the plants by the light? The soil is not dry is it?
hi all i have a question....is it possible to use a 400 watt MH bulb with my 400 watt hps lamp and all? or owuld that f@#$ it up? or is there some type of special bulb i have to buy? i use to know but over time i forgottt...... thanks peace
h4rk4t, you can do that if you use a HM conversion bulb. The "conversion" label means it is intended to work off a HPS ballast. ISTANDALONE, as you sure the system you got is a MH ballast and has a HPS conversion bulb, not the other way around? Light height: 6-7 inches is probably right but don't judge with a ruler, judge by how much heat is generated at the plant level. Put the back of your hand under the light level with the tops of your plants, and if you can hold it there comfortably for 20 seconds or so you are fine.
too late to introduce the light slow, but i'll raise the reflector today. the guy i got the light from (i asked him specifically, several times) says it's a MH ballast with an HPS conversion bulb (MH bulb came with it too). do these even exsist? because the only ones i saw on ebay were MH bulbs designed to run on HPS ballast, and supposedly i have the opposite (MH ballast with HPS conversion bulb).
Yes ISTANDALONE, They go both ways. If your ballast is an MH ballast then you need an HPS conversion bulb. Check these out: http://www.shamanshop.net/store/pro....0/CategoryID/10000.0/SubCatID/930.0/file.htm http://www.shamanshop.net/store/pro....0/CategoryID/10000.0/SubCatID/930.0/file.htm http://www.shamanshop.net/store/pro....0/CategoryID/10000.0/SubCatID/930.0/file.htm Toasty, long time no see buddy. Have not seen you around here for a while.
I've been crazy busy, traveling a lot for business. I think I flew overhead a few times the past couple of months, looked out the window at your home town and wondered under which of those roofs your wicked weed is growing...