Re: Vortexes/Sump sizes

> From: George Booth <booth at hpmtlgb1_lvld.hp.com>
> Date: Mon, 09 Dec 1996 09:36:18 -0700
> Subject: Re: Size of bio-tower

In answer to: 
> > From: Zon Hisham Bin Zainal Abidin <zon at mad_scientist.com> > Date:

> You will have to experiment to determine how deep the water has to be
> to avoid sucking.  It depends on where the water inlet is positioned,
> the shape of the water inlet, how fast the pump pumps, etc.

An inlet facing up is the most likely to cause this kind of whirlpool, so
avoid that.  Also, you can get a much lower level without geting any
sucking by installing a flat plate horizontally about the the inlet; the
vortex won't form (unless you have a REALLY powerfull suction) until the
surface of the water is very clost to the inlet.  The addition of a plate
effectively makes the water surface farther from the inlet.

Also, on the size of the sump:  the most important concern is the minimum
size.  Bigger is better, within reason, but you must AT LEAST have a sump
big enough so that if you top off the water level today, and walk out the
door, and the power fails, and all the spare water in your main tank comes
down, and your foam fractionator and trickle filters drain, and all the
tubes run down dry. . .  the sump should STILL not overflow.