New Grower Controlling temp in tent......

[horton711]

I'm trying to figure out what size fan and filter to get for a 4' x 4' x 80" tent. Currently running 2 MH 300W and 1 Galaxyhydro 300W LED's and the temps are running in the low to mid 80's (°F). The only other heat sources in the tent are two 6" clip on fans for air circulation. 6 DWC buckets are in the tent presently.
My babies are roughly 3 weeks old and I haven't been too worried about the heat but as we head toward summer I want to be prepared and also want to be able to keep the odor under control.
Is there a rule of thumb for sizing an inline exhaust fan and filter? I also wonder if I need to have an inline input fan as well.
I came across a 240 CFM fan + filter on Amazon and wonder if it will do the job. Tried to put up the URL but it didn't look right when I posted the thread. Not sure what I did wrong or if links are not permitted and automatically parsed.
Even though the costs are adding up I never realized how relaxing and rewarding "botany" can be and I can almost consider the monies spent as going toward improving my mental health....lol
Thanks for your help.......

 

[Hopper602]

I would advise to go overkill with the CFM and add a variac speed controller rather than short yourself. Maybe a 6inch 460cfm exhaust and you will be able to turn it up and down.

I won't suggest one of the cheap speed controllers because it caused high pitch noises with my exhaust which led to total failure of it after some time. Spend extra money on the variac if you want your equip to last.

Are you doing an active intake or passive?

 

[A-Train]

Hopper is dead on.. I have a 3x3 but I run a 500cfm on speed control.... the speed control will control your temps that way.

 

[horton711]

Thanks for the help, Hopper and A-Train..... Going with a larger fan and quality speed control makes great sense. I was getting all twisted around trying to account for turns and duct resistance to try and size a fan. I can' figure out this tendency I have to overthink a problem.....lol
For now I believe I can go with an exhaust fan and filter and keep an eye on the temps to determine if I need active air intake. Is what you meant about active / passive intake Hopper?
I'm most likely too late to start a journal at this point but next grow I will try to be organized enough to get one rolling so to speak.....
I really appreciate the replies......

PS..... are there particular brands of fans I should consider? It's looking like the fan/filter combo will be the most expensive purchase to date.

 

[Joedirt]

Amazon product ASIN B002JLGL9M

Ive used this brand, and have had great success.
they are quiet and very efficient.
if you get a 4 inch with the temps you have you will end up getting 2.
so please do your self a favor and get nothing smaller than a 6" An 8 inch would be even better.

 

[Joedirt]

I tried to send you a link for a price, but i guess the mods dont want adds, I get it.
found these 6" @ amazon for $201.00

 

[Joedirt]

I have my fan drawing air threw a can filter and a air cooled light hood.
the fan is outside my room hung from over head with bungy cords

 

[horton711]

Thanks, Joe...... I'm going to check it out on Amazon. Over-sizing the fan makes lots of sense -- it can always be turned down if needed. The diagram really helps me see how I need to get things hooked up!!