Originally Posted by
JMorris271
Sorry I havent gotten back sooner but have been split ithree ways between the pond, work, and the heat;
I can find no external factors that would cause a 9.7 reading for PH
My GH reads 25
KH reads 0
Source water is 5.3
The coping is out of the pond and is flagstone.
I have 2 vortex fillters that are 200 gals each feeding 2 Bead filters in a 4800 ,liner pond
No2 and No 3 are 0
Very very small amt of ammonia.
No runoff has occured that we have seen and I check.
The koi can be seen swimming around sometimes but moving rapidly
Thats pretty much all I know at this time.
Thanks for everyones input.
To , make matters worse I have just had 3 new koi shipped to me. Thankfully, a friend has an unused tank set up and is letting me use it to do the quarentine .
There are two causes of the high pH with these measured values.
The KH is too low as others said, and needs baking soda addition to stabilize pH at a better value.
But the GH is way too low for acceptable pH control. GH is a measure of dissolved calcium and magnesium. When there is enough dissolved calcium and magnesium, AND when the KH is in an acceptable range (meaning between 80 and 300 ppm), if the pH drifts above 8.5, the calcium and magnesium will precipitate the carbonate ions that are causing the high pH and drop the pH value.
So if you want the pH to stay below the 9 value you have measured:
1. Get the KH into the 80 to 300 ppm range by adding two pounds of baking soda per 1000 gallons of pond water.
2. Get the GH in the 100 to 250 ppm range by adding one pound of calcium chloride flake (which is calcium chloride dihydrate, with 77% calcium chloride content, 23% water) per 1000 gallons of water. You may want to also add a pound of Epsom salt (magnesium sulfuate heptahydrate) per 1000 gallons of pond water for sufficient dissolved magnesium also.
Taking those two actions should stablize pH at a value of 8.3, which is ideal for 99% of ponders.
Your koiphen chemist and environmental scientist.