Mh/hps q

[MrC]

I read that MH bulb for veg will keep the plants from stretching as much as dual spec HPS would, or that MH would produce shorter plants in veg compared with dual spec HPS, is there any truth in that?

[M_C]

If you think:-

MH = Blue
HPS = Red
Dual spectrum = a mix of both

MH for the win on less stretch

[Greengrass]

When I'm not f.. king up in other areas I use a 400w Mh for veg and the plants love it with really nice healthy green, and yeah mh does keep them short with tight nodes come flowering but mine at least runs a lot hotter than the dualspec in that I can't get the bulb any closer than 19inches where the hps I can get it a lot closer so just bare that in mind if you plan on swapping Mr C
Atb chap

[MrC]

Thanks for confirming that, 400w dual spec runs between high 26c and 30c, usually hangs around 28 so I may not have a choice, been hot last cple days though. While I'm here is the back of the hand rule for height applicable to seedlings, or should it be a good distance away?

[Greengrass]

Thanks for confirming that, 400w dual spec runs between high 26c and 30c, usually hangs around 28 so I may not have a choice, been hot last cple days though. While I'm here is the back of the hand rule for height applicable to seedlings, or should it be a good distance away?

Ah good question that mate with hps yes I go with the soft part of my arm and leave it a minute to see if it's uncomfortable and plants seem fine with a fan blowing over the tops but the Mh I do check with my arm, even if it feels fine I still back it off a couple more inches as I find the Mh strips the humidity out of my grow room and the leaves aswell

[Shreder]

Mh for the win and i think i have a 6500k 600w rather than the standard 6000k and its beast. Use it on winter grows.

Current grow https://www.thctalk.com/cannabis-for...d.php?t=183445

[MrC]

Ah nice, may have been the cause of my upturned leaves at the start.

I have a Sunmaster 400w Cool Deluxe Metal Halide

A certain site says this:

Sunmaster Cool Deluxe bulbs can provide up to 70% more blue light than standard Metal Halide lamps. Most Metal Halide bulbs have a colour temperature of around 4000K, the Sunmaster is the only Metal Halide lamp in the UK which has a colour temperature of 7200K which is far more in the blue/white spectrum. By providing your plants with this in the vegetative stage will ensure their growth rate will increase, the internodes stay tight so there is no stretching and there is plenty of new shoot growth to give a fuller, healthier plant that is ready and capable of providing and supporting larger yields when flowering

[Greengrass]

I have to add though I grow In a walk in closet and not a tent so I can't really dial in the environment like you guys can with your negative pressure and all that like you can with a tent as the whole environment I suppose makes a whole of difference

[M_C]

I have to add though I grow In a walk in closet and not a tent so I can't really dial in the environment like you guys can with your negative pressure and all that like you can with a tent as the whole environment I suppose makes a whole of difference

So long as it's your place & the wife don't mind a few holes (That she'll never see), things are quite dialable

[MrC]

the wife don't mind a few holes (That she'll never see)

"Is that ANOTHER hole in the wall?"

"No I just moved the last one...."