Re: [APD] Building a new hood

["S. Hieber" <shieber at yahoo_com>]

Putting one fan blowing in and one blowing out is the equivalent of stacking one fan on the other in terms of airflow. Stacking fans like that does increase the airflow--it's like stacking two water pumps in series; the flow doesn't increase. You would be better off having two fans blowing in or two fans blowing out (parallel) -- that will double the airflow provided there is adequate sized intake and exhaust ports. 
 
Fans are stacked on personal computer cases sometimes for one of two reasons:  1) to ensure a particular direction of airflow (for example, to ensure that the airflows past the the cpu fan) and 2) to market to overclockers that think more or something is always better.
 
As Nicholas points out, there's no point trying to move air one way at one end unless you have an opening for the opposite air flow at the other.
 
I've found that vented hoods, along the design of those that AHsupply.com sells do as well passively, by convection, as enclosed hoods with a single fan. I'd try a vented hood first, and add a fan if mere convection proves inadequate in your situation. Passively cooled hoods are much quieter ;-)
 
sh
 
* * * * * * * * * 
The Aquatic Gardeners Association Convention is OPEN for REGISTRATION!
 
Only convention registrants can sign up for the the Field Trip to the Monterrey Bay Aquarium. About 20 slots remain and then the the Field Trip will be fully subscribed and we cannot add any more. 
 
Details are posted at http://www.aquatic-gardeners.org/convention.html 


----- Original Message ----
From: "Wise, Nicholas" <Nicholas_Wise at eon-us.com>
To: aquatic plants digest <aquatic-plants at actwin_com>
Sent: Sunday, June 25, 2006 1:00:31 PM
Subject: Re: [APD] Building a new hood


Just watch out for heat build up in the hood.  I would put a 3" or so
hole in each in and have a pc-fan blowing in on one end and another
blowing out on the other end.


> -----Original Message-----
> From: aquatic-plants-bounces at actwin_com 
> [mailto:aquatic-plants-bounces at actwin_com] On Behalf Of 
> Billionzz at aol_com
> Sent: Sunday, June 25, 2006 12:58 PM
> To: aquatic-plants at actwin_com
> Subject: [APD] Building a new hood
> 
> I have a 120g tank with 4 All Glass 55w compact fluorescent 
> fixtures  sitting on top.
>  
> I am planning on building a hood for the tank and add 2 more 
> 55w compact florescent fixtures from AH Supply, the hood 
> would have all 6 fixtures  inside.
>  
> I was going to remove the guts of the All Glass fixtures and 
> mount  them in the hood.
>  
> Is there anything that I may  need to look out for or does 
> anybody  have any suggestions for this? It seems like a 
> pretty simple plan but I thought  I would check to see if 
> anybody had any suggestions or pointers.
>  
> Thanks,
> Bill
> _______________________________________________
> Aquatic-Plants mailing list
> Aquatic-Plants at actwin_com
> http://www.actwin.com/mailman/listinfo/aquatic-plants
> 

_______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo/aquatic-plants
_______________________________________________
Aquatic-Plants mailing list
Aquatic-Plants at actwin_com
http://www.actwin.com/mailman/listinfo/aquatic-plants