article: Koi Overstocking
Most all water gardeners feel that they always need more for their garden to be
complete, to be balanced, and this leads us to overstocking our water gardens.
Over stocking the water garden can actually lead to more work, and more problems
in the long run. The fish and the plants alike struggle to find the space needed
for their personal growth and living.
In this article I want to talk a little about over stocking koi fish. It is
however, important to realize that every water garden is different. The depth of
each pond can vary, the temperatures are different, and the size of the fish are
different, but here are a few general considerations with the koi fish in the
You can read all types of materials on the koi fish, each with different methods
of finding out how many fish you should keep in a certain sized pond. One thing
you should keep in mind is that the larger the surface area of water, the more
koi you can keep. If you have two ponds, side by side, but one is ten feet
smaller on each edge, you can’t keep as many fish in the smaller pond as in the
larger. The larger square footage gives you more ‘space’ for koi.
Along with the amount of square footage you have on the pond surface, you will
also need to consider your filtration system. While your pond may have the exact
same square footage as a friend of yours does, you use a filtration system, and
your friend doesn’t so you can keep more koi in your water garden safely without
the problems that your friend faces without a filtration system. The quality and
the quantity of water must be taken into consideration when stocking your water
What are a few key indications as to if you have too many fish in your water
The color of your water is an indication if you have too many fish. Is the water
color dark and murky looking? This is from too much waste in the water. A
filtration system or less fish is going to be the answer here. Test the water
for ammonia and nitrates, as a second indication of what the real problem is. If
you are continually getting anything other than a zero rating when testing the
water, you have a population problem.
When fish are getting sick and dying more often than what your fish used too,
you can have too many fish. As your pond is overstocked, the fish are under
stress and catching diseases, or dying off easier than they would with more
oxygen and food in the water. Nitrates and high ammonia is going to hurt the
fish, putting them under stress and causing disease to start.