Salt added to your pond can offer many advantages. First, salt protects the fish from disease and parasitism. Salt is basically an irritant to the skin. The fish responds by building up a slime coat. This slime coat is the fish’s protection against disease and parasitism. The salt also reduces electrolyte loss during periods of stress, or disease, promoting healthier gill function. During times of stress, electrolytes are lost, including potassium, sodium, chlorides, calcium and magnesium. All of these are essential for the uptake of oxygen and the release of carbon dioxide and ammonia. It helps eliminate the toxic effects of nitrite. Salt also assists in suppressing string algae. Salt comes in many forms. It must have no additives. It is imperative that the salt is diluted. No granules should be allowed in the pond. Once salt comes in contact with the gills it will burn and aggravate the gill tissue and eventual fish loss can occur. Most ponds that we care for we add up to .3% or 3lbs per 100 gallon, so a thousand gallon pond will need 30 lbs of salt.
Here it is, simply put..based on a 1,000 gallon pond:
a .1% salt concentration.= Take gallons of pond(1,000)x .01 =
10lb of salt to be added to the pond
For a .2% Take gallons (1000) x .02 = 20 lbs of salt
For a .3% Take gallons (1000) x .03 = 30 lbs of salt
Many suggest keeping the pond between a .2 & .25 will reduce and suppress string algae.
With sick fish or fish in quarantine, a recommended .3% is acceptable to kill many parasites.
Any amount over 3% will harm your plants. Fish can survive in up to .8% but is not recommended as it is bordering the dehydrating of the fish and can lead to death.
Many keep their ponds salted to a 3% at all times, but be warned, do not overdo that. Plants will suffer.
2 cups of salt = 1lb.