How to Fix Hard Water in a Pond
- 1). Insert a test strip and a thermometer into your pond's water. Read the results for pH level, according to the manufacturer's directions.
- 2). Drain out approximately 20 percent of the pond's water using either a pond vacuum or opening the filter's bottom drain plug.
If you have a 100-gallon pond, remove only about 20 gallons. Drain the water into 5-gallon buckets to make it easier to remember how much water you have removed. - 3). Fill a 5-gallon bucket with softened water, meaning water which has run through a water softener.
Place a pond thermometer into the water to get a reading. If the water is too cold, place it in a sunny location to warm up. Dumping cold water into a warm pond shocks the fish. - 4). Place a test strip into the softened water.
Read the results according to the manufacturer's directions. If the nitrate level is high, add a water purifier to the softened water before adding it to the pond. Follow the manufacturer's directions when adding the purifier. - 5). Retest the water before adding it to the pond.
Pour the water slowly into the pond, once it has warmed up to the desired temperature. Add as much water back into the pond as you removed.
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