Using 400w HPS w/ CFL grow

Just a quick question, I was browsing around for some ideas since I shall be constructing a neat little stealth box of my own, I'll make sure to post the pictures when its done.

Anyways, I was thinking, usually poor ganja growers often go CFL since they can't afford the ventilation or the ballast. Well, if I were to veg. my shit w/ the CFLs then go ahead and use 400w HPS for flowering, I would assume there would be a significant difference in terms of quantity/quality. So I guess my question is, what will I be lacking if I veg with CFLs instead of a MH setup? My hypothesis would be just growth differences.

Oh, and can you use the same ballast for 400w MH & 400 HPS?

thx for the read, any response is highly appreciated.

A 400w HPS would be pretty hard to ventilate in a grow box, esp a stealth one (aka no light/air leaks). Im not saying it cant be done but...it would be hard. You can definitely get away with flowering with cfls, they wont be as dense, and you will yield less, but they're way cheaper. To answer your last question, if you buy an HPS ballast, you can buy a conversion MH bulb that will work in the HPS ballast or vise versa. Good luck!

The stealth idea always seems so easy at first...it isnt. Black acrylic sealant is very good. You can use cheap 12V computer fans for exhaust and plant air-circulation but they wont really supply enough freah air. Go to a air-conditioning/refrigeration wholesaler and get a little reversable 240 fan with 6inch blade. Usually comes with a mount frame. Will keep it around 25-28 degrees celcius but heat will still be an issue. This will work quite well if small light leaks are not an issue. If your box is in an area that can be kept dark anyway then no light should creep in on your 12 hr off. If you truly want a stealth box then you will need 6-8 in flexable ducting and cylindrical A/C ducting fans to suit. Light cannot bend around corners. Ducting looks really obvious where small vents can temporarilly be covered over with a towell if need be. Definatly dont run 24/0 in a small box with big lighting, the core temp of everything rises to peak and holds, slowly increasing. Everything needs a cool-down. 20/4 is the optimum light cycle for vegging though 18/6 or 16/8 is better for temp controll. Try cycling the "night" cycle during the day on a small box and keep the overhead light as far away as possible. Probable should start 12/12 @ 6-7 weeks tops for height control. Topping small scale plants is very counter productive. One otherthing, dont overcrowd as you block the light to half the plant. Try using a few cfl's underneath, works a treat. Happy growing!

what are you talking about.
comp fans dont cut it for exhaust. why waste your money on a fridge fan ( thats funny) when admit rthere will be heat problems still. what does using a fan like that have to do with light leaks? you tell him to get 6 to 8 inch flex hose, what if his fan is 4 inch?
18/6 is best for veg.
keep the light as far away as possoble? what ? you want it close as poissible.

the only thing that you said that was accurate was to have the light on at night for heat problems.
you obviously dont know enough to be giving advice. i dont claim to be a hot shot but i know your advice is wrong

My thought is this rather that a 400 watt HPS why not get a small 150 watt HPS if your doing a small stealth grow? it wont put off as much heat and in a small space with a good hort bulb will put up good yeild now if your talking 4-6 med plants or ten small ones I'd go 400-600 but I woldnt call it stealth but 150 would be good for 2'x2'x3' CFL's are working good for me in an experiment I'm doing I'm in the third week of flowering and the bud formation is good the only thing I'm noticing is slightly slower growth than I'm used to under my 400 watt set up I figure it's adding 2 weeks on to normal harvest time my stuff is usually ready in seven looking like nine over in CFL land and you need a bunch of them to get good bud growth I have 11... 4-42 watt the rest 26watt on a 2 foot plant and they generate some heat themself, just another way to go. sorry this is so long

all this advice and nobody knows what the size of the box is

Chill out and have another bong dude (or maybe you shouldn't?)
Think about it...if you mount a computer fan or similar str8 thru the wall or roof then light will escape no? to avoid light escaping you need to use flexable ducting with the fan mounted inside it. Mate if he was using 4" exhaust fans then it would barely shift air through a duct when you take velocity and pressure drop into account.Who uses 4" exhaust fans? In regard to "wasting money" at a refrigeration shop, you have to buy a decent fan somewhere and a cheap bathroom exhaust fan will not work as they are not designed for continuous use. I guess me being a Qualified A/C Tech allows for some heavy discounts but even still they are pretty cheap.
To clear things up mr knowall i said keep the lights as far away as possible, assuming he is growing in a box like he said he was. Most boxes would not be bigger than 6 feet. If your so experienced mate then you would know that putting 400w HPS as close as possible will cause the leaves to dry and burn. Keep them about 2-3 feet, or the light mounted as high as poss, and the plants on the floor of the grow box, allowing 2-3 feet of space.
I have potential heat issues but is no problem whatsoever as the box is sealed during night/off cycle and the door can be left open a crack during the day where light leaks are irrellivant. Mate im not lacking on experiance and my yeilds prove that. You just obviously have a completly different picture to what old' mates "grow box" looks like to me. All good...smoke out. and chill. That is the idea.

mabee i missunderstood, no need for the name calling. i never claimed to be a know it all, mr.
basicaly he needs to rethink the whole idea. a 400 watt in a 2x2x3, have fun with it.

Yeah your probably right, sorry dude. Anyway, i "could" have a 6x4x4 foot box with a 400w MH (veg), 400W HPS(bud) light on top and 3 x 18w growlux fluro tubes and 2 x 23w cfl's for under lighting. 6 plants. 1 x 240v A/C supply fan, 2 x 150mm comp fans (exhaust) and a comp fan for air circulation. Box is very sealed and runs @ 26-28 C. Crack the door and it runs @ 23-25 degrees, hypothetically of course. Whatever works.

sounds nice

i thought we were talking about the original guys issuses? (box size,lights)

bonz said:

i thought we were talking about the original guys issuses? (box size,lights)

Click to expand...

thank you! were and are now.....

why even make the switch from the CFL? just use the Mh or HPS the whole way though or note at all, right? the heats gonna come anhow if you do it that way. and heat is an issue. i use a 400w MH veg and superHPS flowering. its hot. the room is 4 feet deep, 7 feet tall and 5 fet wide. but light is essential. if i were you, id get rid of the CFL.....but that me the thinking........add them, have both at same time...more lumens??? better plants grtowth......im no sceinest. or speller it seems. but makes sence.

the heat......i use a big old fan. only close when have to, thats no good, so the heat is an issue, as is the light, as you know. after looking at everyfan i thnk thats out there, and every other way, ducting is the way to go. tap into something else HVAC. no worries. blow it right out. thnk thall work? is it hard to tap? we have similar issue mate........

thanks
ganics.