hello everyone i have a slight problem i am running 4 x 600w hps in cool tubes and have a 700 cfm blower on them. I was wondering if that was adequate or do i need more. i imagine i need more since the temps are at 28c.

What are the recommended numbers as far as how much cfm per 600w do i need?

i can almost imagine i need double what i got

dude 28 isnt bad, i have 4 x 600 not cooled, a 500cfm fan sucking hot airout and 2 x 100cfm bringing fresh air in. my temps are a bit high but the girls seem to love it! my highest temp has been around 31 - 32 deg cel. if u still want it cooler dont bother getting a bigger fan 700cfm is huge u may need a air conditioner. marijuana can survive extreme hot climates up to 95 deg faranheit.

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LxWxH of room
divided by num of min it is ran

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I'm surprised that is not cooling them. Where are you drawing air from to cool your lights? It's best to pull air from outside the room.

If that does not work try those new ice-box heat exchangers, I'm using one and it works great.

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got a link to the icebox? i have box built and its sucking air from outside the box. i might run a duct and pull the air from outside the house...



2.5mx2.7mx2.2m / ????

not quite understanding what you mean with num of min it is ran?
do you mean number of minutes it is on?
that would be 12 hrs

u should try dropping ur temps to 27c and u might notice some more yield. i have learned that unless there is an adequate source of co2 plants tend to do better for me in lower temps. since the light can be brought closer. with extra co2 the plants do better at 29 since they will use more water, nutes and co2.

Here is your link, also check you ducting try to make it as straight as possible, a 90 degree curve in duct can reduce actual CFM by up to 30%.


http://www.hydroinnovations.com/

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The problem with those tubes is that you are dealing with radiant heat rather than convection heat. In other words, it's not heat coming off the bulb but the rays that give off heat. IMO those cooling tubes don't work. What does work is keeping the light far enough from the plants or using a light mover. The "adjust a wing" with the super spreader is probably the best hood on the market. Funny thing, you can put your hand on top of an aluminum wing 1" away from a 600W HPS bulb and it will be luke warm. That demonstrates the difference between convection and radiant heat.

cool tubes work just fine.?

How is your ducting run? Does it goes go to each one and then out or does it split and then come back together? If they are inline (not split) is there significant heat difference between the first and last?

i noticed 3 x 90 degree turns and im in the process of eliminating that. there are no splits just 1 flow with 3 corners. So im taking care of the corners to block the air flow a bit. The problem is that its been 23c outside at night and its 25c in the house. if it drops to 21c outside i will have no problems. i thnk the whole problem is the air coming into the tubes is not cool enough

Icebox was my other option but it requires a chiller to cool the water. now the water coming through my pipes is at 17c and from what ihave learned is that i can pump that water through with out a chiller but i will be wasting 1000;s of litters of water. i had some other ideas such as throwing ice in the res with the icebox water to cool the water back down to recycle but seems like a pain in the ass and chillers are not exactly cheap. i need a 2hp chiller. anyone know of any cheap ones or dyi to turn a freezer int a chiller?