Conducting a demand test for use of PP
 

A demand rate is the amount of PP required to react with all of the
organic matter in the water sample collected from the system in need
of treatment.

To do a demand test using 5 "like" containers such as 1 quart MAson
jars, collect an equal amount of water from system in each jar.

This process uses an interval of 15 minutes time to determine the
demand. This value is then multipled by 2 to give the recomended
treatment rate.

using the stock solution of 1000mg to one liter of water and mix
thouroughly. The stock solution mentioned in a prevcious post can be
used to make this 1000mg / Liter solution.

In the 5 samples of water add, 2, 4, 6, 8 and 10 Ml of stock
solution. Mix thouroughly.
Wait 15 minutes.

The test treatment that has the "slightest" faint pink color is the
rate you want to use. If in doubt use the sample as to the rate
which still has the slightest pinnk color and always cloose the sample
with the lowest rate.

Example:

After 15 mninutes the 2 mg sample turned brown. but the 4mg sample
stil had a faint pink color The 6mg samples and up are still a dark
purple.....based on colors the 4mg rate is the correct
choice......for demand. Now multiply that number (4) by 2 and you get
a recomended dose of 8mg/L as the correcdt dose rate.

PP is effective in oxidizing organics in water, treating fungal
infections by knocking out the external fungas growths, but antibiotic
may still be needed. All fish even species that tolerate it well may
not tolerate PP, so its wise to have acounter method or reversing the
action of PP. Hydrogen peroxide is very effective at this and will
imediately turn water back to a clean when added. It does however
take a fair amount of Hydrogen peroixide to reverse PP action. Dechors
also are capable of reversing PP's action.

Info obtained from the University of Florida.


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