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this site has been extremely helpful to me - keep up the good work!


i have a couple of questions about lights you might have to excuse my lack of knowledge about this stuff, i am going to get a 400watt setup (light/ballast/shade), i have noticed that you can get shades that have glass on the bottom of them and ducting coming off the sides for heat extraction do you reckon this is worth getting? or do you think just to get a normal one and use more fans in the chamber (the ones with heat extractors cost about $180 more than the setups without). i will be growing in a wardrobe that is about 7ft tall 6ft long and about 3.5ft deep

also does anyone know if there is much difference between brands of lamps? ive got a choice of son-t-agro, ge lucagrow or sunmaster they are all the same wattage but are priced a bit differently, is any one of them better than the rest?

any answers would be much appreciated




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Hi D_amo, let's see if we can't help ya out, eh?


Now, Air-cooled vs "Normal" hoods... Well, this is something you'll get a few diff answers on depending on the setup and where you and the grow is... But generally, you shouldn't need one... Good venting will serve you just as well. An aircooled hood with glass can be brought closer to the plants, yes, and thus more lumens, right? Well, not necissarily... The glass itself refracts a % of that light, and there is a habit of these kinds of lamps to have a film of dust develop on the inside of the glass... If it's left for any period of time it can quickly start eating into your lumens.


My setup is pretty simple, but I've helped heat extraction by simply attaching some 150mm duct from one end of my ablite open ended reflector, and all air extracted must go first pass the light before being exhausted... it quickly takes out the heat from the lamp before it gets a chance to effect the grow, and it still provides enuf suck from my piss ant 120mm comp style fan to keep temps below or around 30 at canopy. 'Course, I have to get a better fan soon, and I've got one coming, so I can grow better and in summer too, but it does the job. The point is, you don't really need to have a glass sheet below, you can set up a single or double extractors, have one small fan servicing the light and one servicing the general grow, which is what I'll be doing myself. This should keep temps much cooler, but still allow for maximum light transmission. The more venting the better, in summer oz can get pretty wild for indoor growers, if you can afford a bigger or better fan, or heck, even multiple, the better.... you should only need a 120mm for the lamp in summer, and perhaps another 150-250mm fan for the grow. Make sure you get a fan rated for continuous use, and generally, the more you spend the better you get. The new one I'm getting is a 250mm "hydro turbo" fan, 2000lpm, if that don't keep my 1800h x 1200l x 500d cupboard cool, just about nuthin would. ;) Oh yeah, get an oscillating fan too, a pedestal one if you've got the space... Plants don't just need fresh air, they need that air to circulate and blow over it... An oscillating fan simulates "wind" in the grow, and makes plants stronger stemmed and generally more vigourous... without such a stirring effect air can quickly become stale in places, and thermocline out into distinct layers within the space.... This can also affect humidity levels, particularly when the lights go out. ALWAYS run at least one extractor at "night" in the grow, and maintain the oscillating too... The moisture laden air quickly cools without the lamp to maintain it's state in the air, and if it's not removed quickly it can cause high humidity and condensation within buds... And we all know what water does when it sits inside buds... BUDROT. Main point: keep the air exchanged and circulating, and the plants will reward ya.


As to lamps, the son-t-agro is generally thought to be the standard maker in 400w hps lamps... it has a boost to it's blue spectrum which makes it suitable for both veg and flower... The other brands are good too, it's just my pref. I find most growers have a son-t agro or son-t-plus (the 600w ver, more than double the lumens from half as much again power use) and they do well with em. It's up to you really. Just remember that you'll have to replace the bulbs every couple of grows, depending on how you're using them, as they'll slowly degrade and produce less and less light.


7ft tall x 6ft wide and 3.5ft deep? So around 2100mm high, bout 1800 wide and a 1000mm deep? Wow, that's a decent sized cupboard man, 21 square feet... I take it you'll be growing a few plants? That's come out to around 19 watts a sq ft with one 400w... Still, you need some space for other things, I'd say you should consider a 600w... brings the levels up nearly double for your watts, and not much more in $ terms either... Just thought I'd suggest that, seeing as you haven't bought the lamp yet. ;)


Hope that helps d_amo, let us know how it's going eh? lol

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The air cooled lights (with glass heat sheild) are mainly used where temperature is a problem in a confined space or small growroom.

Anyone growing in a wardrobe with a 400 watt light should go for the sheilded air cooled version.

As for different brands of bulbs, I havent noticed any difference to my growth rate or yeild but I've only used Silvania , Lucagrow and GE....other brands might make some difference but I doubt it.

I think there should be a longer lifespan with the more expensive brands but with a lot of products I have found that theory isnt always correct. lol

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When i was looking at the ventilated hoods i was told exactly what Luke Skywalker said by the guy at the hydro store. I think he said the glass refracts at least 5% of total lumens, and more when dusty.

If you are going to grow in a wardrobe that size(pretty big at 21 sq. feet) i think a 600 watter would be much better, one 400 is not enough for that space. If you have the extra cash get the 600 watter with ventilated hood, can't go wrong with that. I guess it all depends on how much you want to spend. A light balancer/tracking rail would be perfect in that space with a 600.

I don't think there is too much difference between bulbs, having used lucragrow and son-t i prefer son-t as well.

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This is the most helpful of all sites ive been to i always ask for help and get none. Anyways i am almost ready to set up my hydros and am about to go out Light shopping can anyone give me any ideas i want a relatively large setup so im thinkin maybe 1000w or 600w i own my own property of which i have a huge 30m2 shed which will one day be full. Help please.
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well you can use the formula of 0.5 grams per watt to work out your lighting. You are talking quite a big & expensive setup though. Maybe 3 1000 watters with a fair bit of ventilation. You're also going to need a separate mother/veg area. maybe under a 400watt MH.


In terms of power bill find out how much you pay per kW hour. Usually about 12c. multiply that figure by your total wattage, then divide by a 1000, and that is how much it costs you to run your lights every hour.


eg for a 400watt light it would cost 12c x 400w / 1000 = 4.8c per hour

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