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Koi Pond PH Balance

25 9:58:43

Question
My ph test shows my pond to have high acidity and alkalinity.. I have a good size pond a little over 2000 gallons. It is cement coated with drylock. A water fall and on the opposite side a fish fountain. It is in the full sun most of the day, This is its first year of use. The fish were in a smaller 1000 gallon pond before. I have 14 fish, from 5 to 28 inches in size. They are healthy and so are the plants. I have been treating tap water with Pond Start and Pond Clear-Zyme in a 150 gallon tank and adding it to the pond three or four days later. I also started using algaefix because the pond turned dark cloudy green and I am having a problem with blanket or string algae. I have added it to the 55 gallon filter where it goes out into the water fall 4 times three days apart. I haven't seen much of a change. All other levels in the PH are normal. What do you suggest I do to get the acidity and alkalinity levels more normal. Our water comes from a spring, but it has a lot of minerals and is very hard. I live at 7250 feet above sea level in the mountains of New Mexico.

Answer
Mary,

Throw your test kits away.  Let your plants and fish test the water for you.  If they are doing well, then don't worry about what the kits say.  You are making this WAY too difficult.

Very simply:

EXCESS NUTRIENTS IN THE WATER = GREEN WATER
REMOVE NUTRIENTS = WATER CLEARS

Remove the nutrients by covering the bottom of the pond with a thin layer of large gravel and placing a quantity of stones around the perimeter down in the water.  This is for the beneficial bacteria to live on.  Fortify your bacteria colony with any commercially available bacteria concentrate.  Liquid or dry, from your local pond store or off the internet.  All this converts the wastes from your fish into Nitrates that the plants can remove.  Add a large mat of floating plants.  Something like water hyacinth, water lettuce, or parrot's feather.  Within a week or so this will all start to work and your pond will clear if...  and it's a BIG if.  If you stop putting more nutrients into the water.  Stop feeding the fish.  They won't starve.  Let them eat string algae and nibble on the plants.  This is where most of the nutrients come from that make your water green.  If you can stop for just a week or two this will work a lot faster, then you can begin to feed just a little.  As the bacteria colony gets established, you can feed more and more without causing the water to turn green.  Be patient, though.  It can take several months to more than a year before it is completely balanced.

Now, the string algae.  Just remove as much as you can by hand.  This also removes unwanted nutrients.  What is left can be killed with sodium perchlorate.  You can buy it in the form of GreenClean, SAB, D-Solv, or common OxyClean down at the store.  Just sprinkle it on the remaining string algae and it will knock it right out.  Completely non-toxic to fish or desirable plants.

Now, get rid of the 150 gallon tank.  Unless you're adding more than 200 gallons of water at a time, you don't need to even treat for the chlorine.  Just throw the hose over in it and top it off once a week.

You need a pump running 24/7 to keep the water circulated.  The pump needs to be at least a 2000 or 3000 gallon per hour pump.  

Get this all in place and sit back and enjoy your pond.  

Good Luck,

John