> From: bowkerg at NTU_EDU.AU (Gail Bowker)
> Date: Tue, 21 May 1996 09:25:57 +0930
> Is there any rough guide as to how many gals or litres of water per
> hour a filter should be able to handle?
One Rule of Thumb is the filter should be able to turn over the tank
volume 5 times per hour. Two things to take note of:
First, most tank manufacturers are a bit optimistic in their volume
estimates. A "20 gallon" tank does not contain 20 gallons of water.
Also, you need to compensate for the volume of gravel and driftwood
used (the volume of fish is probably insignificant in this respect).
For example, our "90 gallon" tank actually has 73 gallons of water
when all is said and done.
Second, most filter manufacturers are a bit optimistic when they
rate the flow of their filters. While their exact methods are unknown
(and probably a trade secret), I would guess the ratings are based on
zero backpressure (or maybe even pumping "against" a vacuum), using
the largest hose available, having light water in the tank and
probably pumping downhill.
Perhaps the two optimisms cancel out each other and a "100 gallon per
hour" filter is perfect for a "20 gallon" tank. But it's something
of which you should be aware.
My choice is from ... Does anyone have any comments on any of these?
> Eheim Power Filter
Can't go wrong here. Very high quality. Very little noise.
George in Sunny|Rainy|Cool|Windy|Pleasant|Gorgeous|Hideous Colorado