100x100x200cm Tent, 600w HPS - WHAT VENTILATION ???

[NorthofEngland]

Hello, A 100cm x 100cm x 200cm grow tent, with a 600w HPS. What ventilation would you recommend? I know I need fresh air in (near bottom), stale air out (other side, near top) and a system to neutralise odours. Plus a fan to encourage movement. Any advice about the size of these things would be helpful. Many thanks/

 

[jondamon]

Read this

http://urbangardenmagazine.com/2010/07/planning-your-grow

Then do it yourself.

And remember you can't just dump all that heat from your light into the room with the tent in it. This will cause the surrounding room to increase in temperature causing your tent to steadily rise in temp.


Read the article and then apply the math to your own area.


Then you can calculate your own needs.



J

 

[NorthofEngland]

Jondamon, You star! Already worked out just under 90 Cubic Feet per Minute (or 150m cubed per hour). I'll read the rest tomorrow. I've just bought The Cannabis Grow Bible by Greg Green which goes into great detail about all kinds of things BUT doesn't say much about ventilation. I intend to have the extracted/charcoal filtered 'air out' exit through a window. The 'air in' will be sucked from the next room. Plus I'll have a fan helping to keep things moving. How does this sound?

 

[jondamon]

Jondamon, You star! Already worked out just under 90 Cubic Feet per Minute (or 150m cubed per hour). I'll read the rest tomorrow. I've just bought The Cannabis Grow Bible by Greg Green which goes into great detail about all kinds of things BUT doesn't say much about ventilation. I intend to have the extracted/charcoal filtered 'air out' exit through a window. The 'air in' will be sucked from the next room. Plus I'll have a fan helping to keep things moving. How does this sound?

Sounds good.

Are you planning on using an air cooled reflector?
I ask this because 600w in a 3x3x6 tent is gonna get pretty ducking warm if you don't air cool.




J

 

[NorthofEngland]

http://www.ebay.co.uk/itm/600w-Lumii-Dual-Spectrum-HPS-Grow-Light-Kit-for-Hydroponics-Plant-Quality-/111193950850?_trksid=p2047675.l2557&ssPageName=STRK:MEWAX:IT&nma=true&si=uuDoWRsM31MUCmnUyCfG0tA9ujY%3D&orig_cvip=true&rt=nc This is what I've bought - plus a second ballast and plug cord. I cannot afford an air cooled unit, at the moment, as I'm an absolute beginner who's buying every single thing that is needed. The Lumii 600w is horticultural design - especially for supplementary lighting in a greenhouse. The bulbs are usually a minimum of £20 and I've bought 2 brand new and 1 in the unit. It seemed like the best available choice for my spending power.

 

[jondamon]

Without air cooling the light (£40 for a cooltube reflector) you may suffer high heat in the tent.



You do realise a decent inline fan to exchange the air will be around £75 and a quality carbon filter will set you back around £60-£120 depending upon brand.




J

 

[jondamon]

Just so that you're aware you're going to need at least a 6" fan capable of moving around 500m3/h of air.

Something like the RVK150E2-A1 by SYSTEMAIR.


Then a filter rated for more m3/h than the fan can move.



J

 

[NorthofEngland]

I have a 12" fan that I will make do with for the first 4 to 6 weeks. I can see CoolTube Reflectors for £28 on e-bay (ma be the best option for the 2nd ballast?). I'm going to have to buy the in-line fan and carbon filter a month, or so, into the grow. The in-line fan .... Does it control air in and extraction?

 

[jondamon]

I have a 12" fan that I will make do with for the first 4 to 6 weeks. I can see CoolTube Reflectors for £28 on e-bay (ma be the best option for the 2nd ballast?). I'm going to have to buy the in-line fan and carbon filter a month, or so, into the grow. The in-line fan .... Does it control air in and extraction?

The FAN I was talking about is a 6" inline fan for extracting your air.

With 600w and no inline fan your temps will sky rocket above 40c.



J

 

[NorthofEngland]

So you'd strongly suggest that I had the full ventilation set up before introducing the cuttings? What about the 'air in' part?

 

[jondamon]

So you'd strongly suggest that I had the full ventilation set up before introducing the cuttings? What about the 'air in' part?

Yes ventilation and lights go hand in hand with hps. You can't have one without the other.

The air in part can simply be opening 3 lower flaps on your tent to allow air to passively come in through the holes as the fan removes the heat.


J

 

[jondamon]

The bare minimum you'll need

Your tent
Your reflector, bulb and ballast
A high velocity inline fan such as RUCK or RVK
an oscillating fan
Medium - soil coco hydro etc
Seeds
Nutrients.

THIS IS THE BARE MINIMUM.

Once you power up your light in that little tent its going to quickly become apparent that they get hot.

Test runs are best before you even contemplate growing to make sure you can give them as near to a perfect environment as possible.

Anything over 28C is too hot and will hinder growth and flower production.


I hope you don't think you can run 2x600w in that little tent???

You'd need something like a 2x1.2x2 tent to run 2x600w.

Then you'd need a larger fan again or both air cooled to control temps.






J

 

[NorthofEngland]

No. Just 1 x 600w in a 100cm x 100cm x 200cm tent (the 2nd ballast doesn't work so I got one ballast, one reflector and 3 x 600w bulbs for £5. I need 150 m cubed per hour - there are 4in fans sets available that extract 180m cubed per hour (£47) or 5in 185m cubed per hour (£45) http://www.ebay.co.uk/itm/4-In-Line-Fan-Carbon-Filter-Duct-Kit-Hydroponic-Grow-Room-Tent-Ventilation-/120802491988 http://www.ebay.co.uk/itm/5-In-Line-Fan-Carbon-Filter-Duct-Kit-Hydroponic-Grow-Room-Tent-Ventilation-/111174519553 WHAT DO I DO ABOUT PUMPNG AIR INTO THE TENT (I have an oscillating fan, a desk fan, to keep things moving inside).

 

[NorthofEngland]

Would you also use an air cooled reflector as well as the inline extractor?

 

[jondamon]

Here is a general rule of thumb for size lights and fan sizes.

250w 4" fan
400w 5" fan
600w 6" fan
1000w 8" fan

Like I mentioned. In order to remove your lights heat and ventilate you'll need 500m3/h.


I use a 400w and use a 480m3/h fan.



J

 

[jondamon]

The reason I am advising a large inline fan is because you are choosing a big light in a small tent.

Realistically you should have purchased a 1.2x1.2x2 tent or a 1.5x1.5x2 tent for a 600w.


J

 

[jondamon]

When you run an inline fan inside your tent it passively "pumps" air into the tent using any available holes.



J

 

[jondamon]

Would you also use an air cooled reflector as well as the inline extractor?

Yes.

Have your carbon filter first, connected to the air cooled reflector with ducting, connected to the fan with ducting and out of the tent.



J

 

[jondamon]

No. Just 1 x 600w in a 100cm x 100cm x 200cm tent (the 2nd ballast doesn't work so I got one ballast, one reflector and 3 x 600w bulbs for £5. I need 150 m cubed per hour - there are 4in fans sets available that extract 180m cubed per hour (£47) or 5in 185m cubed per hour (£45) http://www.ebay.co.uk/itm/4-In-Line-Fan-Carbon-Filter-Duct-Kit-Hydroponic-Grow-Room-Tent-Ventilation-/120802491988 http://www.ebay.co.uk/itm/5-In-Line-Fan-Carbon-Filter-Duct-Kit-Hydroponic-Grow-Room-Tent-Ventilation-/111174519553 WHAT DO I DO ABOUT PUMPNG AIR INTO THE TENT (I have an oscillating fan, a desk fan, to keep things moving inside).

I have one question for you!

Do you want to buy right and buy once, or do you want to buy wrong and buy twice?

Believe me I've been there and done that.




J

 

[NorthofEngland]

Obviously I'd rather buy once - than buy cheap and go through all the trouble of beakdowns and, inevitably, buying a replacement that's better. Why ? Are my choices ringing alarm bells?