I would adjust the heater so that it keeps the tank up to a higher
temp...like say 80 or 82 deg.......then the swing will be less
overall......84deg is a bit high, but IMHO is not really that far out
of line when you look at the online temps of various reefs of the
world. It is however a drastic reduction in fudge control if you run
into a situatin so you have lots less wiggle room if it was able to be
run at a max of 82 F. If you already have fans ordered I would just
bump up the heater a few degrees to reduce some of the swing, ,
install the fans and work at obtainig a decent happy medium of temp
with a bit of playing with fans and heater settings. Are you going to
use a variable power supply for the fans........A variable supply is
best as you can further control speed and noise levels of fan and have
more precise control available.
Most fans will run on 4.6 to 14 volts of DC power..

On Sun, 21 Jan 2007 19:40:39 -0500, KurtG
wrote:


I ordered some more slimline fans, but my temp still swings from 77 to
84 in a day. Is 7 degrees too much?

I was hoping to wait till next month to buy a chiller, but it seems like
I need to do something sooner.

--Kurt



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I forgot more about ponds and koi than I'll ever know!