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RE: PMDD Dosage and Algae

> one important piece of information I forgot to mention.  Our city's
> water treatment reps insist that "Phosphate levels in Edmonton's water
> are non-detectable.  The detection limit is 0.01 ppm."  Even though
> phosphate is not one of the parameters reported, their Parameters of
> Edmonton Drinking Water - July 99 is located at:
>     http://www.aqualta.com/pages/about9a.html


It sounds like you have excess phosphates in your tank, and despite the
insistence of your water treatment reps, I suspect your tap water is the
source.  Many municipalities (including mine) ADD phosphate to tap water
because:  1) it is an effective corrosion inhibitor for metal pipes, and 2)
it is also helps prevent the formation of scale.   You can check out my
water chemistry parameters at:
http://www.ci.austin.tx.us/water/watersummary2.htm.  Note the differences in
phosphate between our incoming (raw) water and the outgoing (tap) water.
Phosphate comes in at about 0.06 ppm from the Colorado River, and comes out
of our tap at about 1.0 ppm.

Because of this, I never change more than 10-15% of my water per week (e.g.,
I don't increase my phosphates more than 0.1-0.15 ppm) and I don't have any
algae problems.  I've been doing this for 4 years.  If you can go two weeks
without a water change (replacing your evaporated water with RO or
distilled), then your phosphates will drop to 0 and your algae should begin
to fade.  If not, then your tap water isn't the culprit.

BTW, my tank is half (90 gals) the size of yours, and I add 10 ml of PMDD