Can I use sodium-softened water in a koi pond or aquarium?
Q:
Can I use sodium-softened water in a koi pond or aquarium?
A:
Some fish thrive in softened water, while some others may prefer harder
water. Knowing basic information about the water supply is essential to
determining if or how much soft water should be used for aquarium water.
Extremely hard water will contain high levels of Total Dissolved Solids
(TDS), which may not be ideal for fish. Since water softening only
exchanges sodium or potassium for hard water cations (calcium and
magnesium), the TDS level does not change. Some soft water supplies are
perfectly fine for fish, but soft water made from extremely hard water
may need to be diluted with distilled, deionized or reverse osmosis
water before it is acceptable.
When beginning the changeover, note that
any drastic change in the water supply could jeopardize "sensitive"
fish. Partial water changes could be made at intervals using the
softened water, but too much or too often may stress the fish. Please
consult your local fish expert or veterinarian to determine if the raw
and/or softened water supply in your area is appropriate for the kind of
fish in your pond or aquarium, and whether additional variables need to
be monitored.