The Importance of Carbonate Hardness (KH) in your KOI Pond

The most overlooked, yet most important water parameter of your KOI Pond is KH.  KH is the measure of the Carbonate Hardness in your Pond.  Carbonate Hardness is simply the amount of Calcium Carbonate in our ponds.

Why is it important to have a sufficient amount of Calcium Carbonate in your pond??  The nitrifying bacteria that remove harmful Ammonia and Nitrite from your water cannot survive without it!!  So, to put it simply, No Calcium Carbonate means NO BIOLOGICAL FILTRATION.  Without Biological Filtration your water quality will quickly become polluted and toxic for your fish and as a result your fish are much more susceptible to disease or even death!

What Happens if My KH Levels Get too Low??  The effect of low KH levels may not be immediately seen.  Low KH levels will ultimately lead to other water quality issues due to insufficient Biological Filtration.  A buildup of harmful Ammonia and Nitrite will start to accumulate in your pond.  Your pond will also be susceptible to harmful pH swings which could lead to a pH Crash, which could kill all of your fish very quickly.

How Can I Prevent My KH Levels from Getting Too Low??  The best way to prevent your KH levels from getting to low is to test regularly and adjust the levels as needed.  We recommend buffering your KH to a level of at least 150 PPM.  Some Pond hobbyists prefer to keep their KH level over 200 PPM.  KH levels cannot be “too high” however anything higher than 200 PPM is not necessarily of any real benefit.

How do I raise my KH Levels??  If you don’t have Microbe-Lift/KH Bio-Active Booster, then, regular Arm & Hammer Baking Soda will be fine in most cases.  This can be purchased at your local Grocery store for around $1 for a 2 lb. box.  However, keep in mind that the Microbe-Lift/KH Booster comes in 2 lbs., 8 lbs., 20 lbs. and 50 lbs. and contents are more stable, so may last longer in the pond than sodium bicarbonate.

How Much Baking Soda Should I add??  We recommend adding 1 cup of baking soda per 1,000 gallons of pond water daily until your KH level has increased to 150 PPM.  Test your KH level after 24 hours before adding more Baking Soda.

When Should I add more KH??  As needed, whenever your KH Levels Drop.  Be sure to test your KH levels at least once per week and especially after rain.  Rain is acidic and will lower your KH level.

What KH Test Kit Should I use??  We recommend using the API brand test kit.  It can be purchased at many pond shops or Amazon.com.