Flowering with MH

[ojitos1985]

Will work? Will be dumb? Will be no potent?

ojitos1985 Reviewed by ojitos1985 on 12-28-2007. Flowering with MH Will work? Will be dumb? Will be no potent? Rating: 5

[GaGrown]

I've done it when that was the only light I had available. You can go from start to finish with your MH. It really should be a 400.

Ga Grown!

[hatch]

Yes most definitely. I've been using that method for many years. I start the first month with a MH and finish with HPS. The plants love it and so do I. As far as potency I have been trying for years in testing and always wonder how it was after I wake up and have came to the conclusion that it damn good haha.

[OLDJIMMYBONES]

will work fine, not dumb

[JackHerer]

It wil give you some result, but its certainly not the optimum choice as the MH emits the wrong spectrum for flower. MH is better if your using only sinlge types of light for vegging then switch to HPS. If you can only afford one light set-up then the majority of reading I have done recommends that you go with HPS for the full term of the grow. This may result in more strecthing during veg but will yield better bud results than MH.

This is different from the position that you can afford multiple light set-ups & will run a balance of blue & red spectrum throughout the grow.

[Mr. Clandestine]

Also remember that many places sell conversion bulbs, where you may be able to purchase a conversion HPS that will work in your MH system. MH will grow a plant from veg through flower, but the HPS is a much better spectrum for flowering...and can be made to work in a MH system. Good luck.

[JackHerer]

Its unlikely you will find a conversion kit to run a HPS from a MH ballast. Loads of stuff on here about switchable ballasts etc but the basics are that HPS systems need a starter that the MH doesn't so you can get MH bulbs to work in HPS ballasts but a MH ballast does not have the required starter to fire up HPS bulbs.

[Mr. Clandestine]

Its unlikely you will find a conversion kit to run a HPS from a MH ballast.

They're probably not as popular as the HPS to MH bulbs, but they do exist. If there's a mechanism that's needed to ignite the gases within the arc tube, then it must be built into the bulb...at least, on the one that I remember seeing.

[JackHerer]

They're probably not as popular as the HPS to MH bulbs, but they do exist. If there's a mechanism that's needed to ignite the gases within the arc tube, then it must be built into the bulb...at least, on the one that I remember seeing.

Thats why I use the term unlikely rather than "you will not" or "there is no such thing" since anything electrical items dedicated to one system will sooner or later have a conversion system designed by a budding engineer looking to get a good mark on a thesis.

Two seconds on google give you these ones.

Buy HID Metal Halide & HPS Conversion Bulbs Here!
Buy 250W EYE Hortilux HPS Conversion Bulbs Here!

but from them you will see physical shape may then cause issues with fitting in some reflectors. Like all the will this bulb work with X system questions there is a lot of maybe but maybe not unless you are using a system which is widely used, has been tried using the adaptions your asking about & has been posted somewhere for people to read about.

The best answer IMHO is if you already hae the lighting system & ballast do a search on your make & mdel enclosing the whole lot in "" quotes. This will give an idea of what people have already used it for.

If you don't already own the MH ballast system then whats the pont in fighting the flow of electricity to just be different you might as well get the most common system & benefit from the reduced purchase costs.

[Mr. Clandestine]

If you don't already own the MH ballast system then whats the pont in fighting the flow of electricity to just be different you might as well get the most common system & benefit from the reduced purchase costs.

I was under the assumption, from the way the initial question was asked, that the poster was already using a MH system and wanted to know what would be more appropriate for flowering. In which case, barring any physical complications with the reflector, a conversion HPS would be feasible and economical. (Much better to save money and buy a conversion bulb than it is to buy an entirely new lighting system, right?) If you have an air-cooled & enclosed hood, I guess I could see a potential space issue...but there probably wouldn't be much interference in a light with an open hood.

If you have the money to get a switchable system, then by all means, get it. But if you happen to have an HPS-only, or a MH-only system, then conversion bulbs are the way to go if you want to veg under MH, and flower under HPS.