What size HPS to get?

bigjesse1922 said:

i found inline duct fans at homedepot.com for 34 dollars for the 6" variety

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mercilus said:

I think I may have seem something similar at our local lowes here.

Take a look at this guy.. It is what I am considering buying.

http://www.hydroponicgarden.net/content-product_info/product_id-1204/6_inline_duct_fan.html

About $20 more but should be quieter..and maybe more powerful? I have not owned one of these but it seems the right price for my cabinets light cooling needs.

Then I will use about 3 of these to cool the inside of the cabinet on a thermostat.

http://www.newegg.com/Product/Product.aspx?Item=N82E16835185054

133 CFM for only 9.99 +SH... Great deal IMO

Three should handle venting the cab I imagine but if not... I will get a few more...

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OregonMeds said:

If you just DIY cooltube it you would be fine. You'll want a good fan for the cooltube, maybe "solar and palau" they are the best I've ever seen. That and a $20 bake a round.

Cooltube, a couple small fans for air circulation and second small exhaust and you would be fine.

You can't just grow in the open without a light sealed area or you won't be able to flower properly.

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mercilus said:

I already have a bake-a-round cooling a 150 Watt HPS.

What size CFM do you think I will need for cooling the light sufficiently with its own air intake? 170+ ok for the cool tube or should I jump to the 250+cfm fans?

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GypsyBush said:

If you are using CENTRIFUGAL fans, that do not loose CFM easily, I would say that 170 CFM is ok for one light...

The problem starts when people try to use duct fans... they are meant as boosters, the rating they have is what they allow to pass without restriction...

One of those 4" 80 CFM duct fans will allow 80 CFM to pass by it without any restrictions.... if you are pushing more than 80 cfm, that fan will cause an restriction...

It may even push 80 CFM by itself... if you add an inch of ducting, you will loose a lot of grunt...

Al B. Fuct cools 2 x 1000watt HPS in cooltubes with a 200 CFM centrifugal fan....

My suggestion would be to get one of the 4" centrifugal blowers, like this one...

But that is just MY opinion... go with what you know....

GrowBright 4" Inline Fan

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mercilus said:

Another thought I had would be to mount the light completely out of the box.

Cut a square out the size of my hood and mount it in. This shouldn't be difficult to cut since I made my cab out of some plywood. This will give me an extra 7+ inches to grow in height as well.

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fat sam said:

go with the 600, they have almost 2 times the output of the 400s, a few of my plants are about a foot away from the light so i keep a fan blowing at all times and have no problems

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