Here is a
ratio that will give a tool to know how many gallons of
water you will need for the total number of inches of
fish in your pond.
Figure the
total inches of fish (measure from head to the end of
the tail of each fish). Then square that number,
multiply by 2, divide by 231, and multiply by 20 for the
ideal number of gallons that will accommodate the inches
of fish in your pond.
Example: 2
Goldfish that are 4, 2 Koi that are 6=>total inches of
fish=20; 20x20=400; 400x2=800; 800 divided by 231=3.46;
2.46x20=69.26. So you would need a 70 gallon pond to
accommodate 20 of fish.
Now you
can see that in a 70 gallon pond you could keep 20 fish
that are 1 long or you could keep 2 fish at 4: and 2
fish at 6. The larger the fish the more area it needs.
