RE: Aquatic Plants Digest V6 #31

["Adam Shaw" <adams1 at comcen_com.au>]

>Date: Fri, 24 Jan 2003 04:52:55 -0800 (PST)
>From: "S. Hieber" <shieber at yahoo_com>
>Subject: Re: New setup opinions -- and some old questions

>At the risk of being corrected (who, me?), I'll add some
>further thoguhts about using a UV.

<SNIP>  I'd think that about 8 watts per 30 gallons would be plenty.  15
might be enough for 100 gal.  25 will be more than enough.  Put the
UV on a bypass (or Tee) off of a waterline to control the flow
rate/dwell time.  Most of the flow rates you see posted by UV
manufacturers are the same as they give for sterilizing water in
single-pass systems (like drinking water).  I think they tend to be
generous (to themselves)
when they suggest lamp sizes for aquariums  -- but then, I'm known to be
cynical now and then. <Snip>

Not stepping on your feet here Scott.. but just adding to what Scott
said, I believe the wattage of UV sterilizer required would depend on a
variety of factors - efficiency of the sterilizer design, quality of the
UV bulb, as well as environmental factors such as the quality of the
filter system in removing suspended matter, lighting, amount of plants
and stocking rates as well as quality of water change water (introduced
micro-organisms and algae) etc.

I run a good quality (though rather pricey) Rainbow Lifegard 8 watt UV
module on my 60g planted. The water is crystal clear. It runs 24/7
though I could probably cut it back to half that and get the same
results. I took the uv sterilizer off the tank for a month and the
difference was clearly noticed. I am going to run the same module on my
new 140g planted. With this particular module the maximum flow
recommended is about 240gph, and I have operated on the idea of moving
about 1/2 of the tank volume through a high quality module every hour
for a long time now, with what I consider great results. Perhaps this
will be a little small for a 140 and I may upgrade to a 25 Watt. It is
well worth buying a high quality sterilizer if you are going to buy one
- whilst costing more initially, and perhaps spares might cost a little
more, they run more efficiently and more effectively. I haven't thought
twice ever about the module that I have, whilst I have seen some others'
tanks using different brands and models and, though realizing their
environmental factors might be different, the results are not as clear
as with my unit / system. Bit of a worry when trying to keep those
nasties out!

Adam Shaw
Australia