Freshly Filled Pool Chemical Guide
What start-up chemicals are needed for a new pool, or for a pool that has been drained and refilled with fresh water?
That depends on the water balance of your source water - some tap water makes excellent pool water, while other sources need major adjustment, for water balance that works well with chlorine and won't stain, scale, fade or corrode your soft and shiny pool surfaces.
Refilling a Pool with Fresh Water
You have choices - fill from the hose, fill from a truck or fill from a nearby fire hydrant. Most people opt for the garden hose pool filling method, often using two hoses where possible.
If your water is from a well, or if your source water contains silty dirt, minerals and metals, or high levels of chloramines or phosphates, you can filter the water as you fill the pool. Pleatco's pool fill pre-filter handles up to 40,000 gallons, and removes impurities and stain causing particles.
Testing your Freshly Filled Pool Water
To find out the water balance of your source water, just use a pool test kit or test strips. Be sure that your kit or strips are fresh, last years supply may produce inaccurate results.
To produce the full battery of water tests (chlorine, pH, Alkalinity, Calcium Hardness and Cyanuric Acid), you will need a complete test kit like the Taylor Deluxe K-2005. If you prefer test strips, AquaChek Select 7-Way, and LaMotte Insta Test 6 are both complete test strips.
Taking a water sample to the pool store may not be the best option, as their system is designed to sell you chemicals, after which you will need to test the water again, and test all summer - so you may as well buy the K-2005 (the same test kit that pool stores use), or buy some fresh 6-way or 7-way test strips, which aren't as accurate, but may be close enough.
Adding Chemicals for a Newly Filled Pool
- Alkalinity Adjustments: It's recommended to start with any adjustments to total alkalinity first, because of it's effect upon pH levels. If your TA is below 80 ppm, add Alkalinity Increaser. If your TA is above 120 ppm, use pH Decreaser to reduce levels within range.
- pH Adjustments: When pH is too low, your chlorine works very well, but when it dips below 7.0, the water becomes acidic and slightly corrosive. When pH rises above 8.0, chlorine is very slow to react, and the water becomes very basic, and prone to cloudy water and scale deposits. Use pH Increaser or pH Decreaser as needed to maintain 7.2-7.6.
- Calcium Adjustments: For pools in hard water areas, tap water of 400-600 ppm is not uncommon. The range of 180-220 ppm is somewhat flexible as many pools operate with much higher calcium hardness levels, without a problem. If your water is soft however, below 180 ppm, this can cause aggressive water conditions, causing etching, staining and deposits. Add Calcium Hardness Increaser to raise calcium hardness levels.
- Cyanuric Adjustments: Any body of water will always have a testable level of pH, alkalinity and calcium hardness, whether low or high, but on a newly filled pool, cyanuric acid (aka stabilizer) levels are usually zero. Chlorine tablets contain stabilizer, but it can take years for levels to build-up. Boost it up to 30 ppm by adding 3 lbs of Stabilizer per 10,000 gallons of pool water, to protect free chlorine from the sun.
- Chlorine Adjustments: Lastly, after you have tested and added any adjustment chemicals needed, separately to the pool, you can raise the chlorine level. Granular chlorine (pool shock) is most often used to quickly raise the chlorine to levels high enough to oxidize (destroy) any contaminants, pathogens and combined chlorine molecules. Follow label directions for dosage and treatment guidelines for freshly filled pools.
Tips for Adding Start-Up Pool Chemicals
- Add Stain & Scale chemical first, especially for new plaster.
- Try PoolCalculator.com for amounts of start-up chemicals
- Add one chemical at a time, using a pool brush to distribute.
- Run filter pump while adding chemicals to circulate.
- Re-test the pool water after 8 hours of filter run time.
- Add chlorine shock when the sun is not directly overhead.
- Add algaecides last, after chlorine level drops below 3 ppm.
- See our Pool Start-Up Kits for all the chemicals needed.
Once the pool is opened, you will need to circulate, filter, clean and treat the pool water - every day. Consistent water balance, constant chlorine levels and effective filtering is important to prevent water problems.
And, as the water temperature and pool usage increases through the summer, you will need more hours of daily filtering, and more chlorine tablets to maintain sanitation and clarity.
Chemicals Needed for Pool Start Ups
- Stain & Scale Preventer
- Granular Shock Chlorine
- Chlorine Tablets
- pH Increaser and/or pH Decreaser
- Alkalinity and/or Calcium Increaser
- Cyanuric Acid (Stabilizer)
- Algaecide and Clarifiers if needed
- Complete Test Kit or Test Strips.
We also have spring pool start-up kits, pool chemical packages specifically geared to new pool start-ups. Start-Up Kits for pools contain Stain & Scale, Pool Shock, Algaecide, Clarifier and Sun-Sorb oil absorbing sponge. Bundled pool start-up chemicals saves a considerable amount over purchasing items separately.