what does adding calcium do to plaster pool

3 min read 24-12-2024

what does adding calcium do to plaster pool

Adding calcium to a plaster pool primarily affects its water chemistry and, consequently, the longevity and appearance of the plaster finish. Understanding this is crucial for maintaining a healthy and aesthetically pleasing pool. This article explores the role of calcium in plaster pools, the implications of calcium hardness levels, and how to manage them effectively.

Understanding Calcium Hardness in Pool Water

Calcium hardness refers to the concentration of calcium and magnesium ions in your pool water. While magnesium plays a role, calcium is the dominant factor. It's measured in parts per million (ppm) or grains per gallon (gpg). A balanced calcium level is essential for a stable and healthy pool environment.

Why Calcium is Important for Plaster Pools

Calcium acts as a buffer, protecting the plaster surface from excessive etching and corrosion. When calcium levels are too low, the plaster can begin to dissolve, leading to:

Rough Surface: The plaster becomes pitted and rough, making the pool feel unpleasant to touch.
Scaling: Calcium carbonate can precipitate out of solution, creating unsightly white spots or scaling on the pool surface. This happens paradoxically when calcium is too high.
Deterioration: The plaster's structural integrity weakens over time, leading to premature damage and costly repairs.
Cloudy Water: Low calcium can contribute to cloudy water conditions as the plaster releases fine particles.

Ideal Calcium Hardness Levels

The ideal calcium hardness range for plaster pools is generally between 200 and 400 ppm (or 12-24 gpg). Maintaining this range helps prevent the issues mentioned above.

Effects of Low Calcium Levels

Low calcium levels are more damaging to plaster pools than high levels. When calcium is depleted, the water becomes more acidic and can attack the calcium carbonate in the plaster itself. This leads to etching, roughening, and eventual deterioration. Regular testing and adjustments are vital to avoid this scenario.

Effects of High Calcium Levels

While less damaging than low calcium, excessively high levels can lead to scaling and cloudiness. Calcium carbonate precipitates out of solution, forming those unsightly white deposits. This is usually less destructive than etching but still aesthetically unappealing and can require more cleaning.

Managing Calcium Levels in Your Plaster Pool

Maintaining the ideal calcium range requires regular testing and adjustments. Here's a breakdown of the process:

1. Testing Your Water

Use a reliable test kit to measure your pool's calcium hardness. Test strips are convenient for quick checks, but liquid test kits generally provide more accurate readings.

2. Adjusting Calcium Levels

Raising Calcium: If your levels are low, you'll need to add a calcium chloride product specifically designed for pools. Always follow the product instructions carefully for dosage. Add the calcium chloride slowly and evenly to ensure proper distribution.
Lowering Calcium: Lowering high calcium levels is more complex and usually requires partial draining and refilling the pool. Consult with a pool professional for this procedure, as it's crucial to maintain proper water balance throughout the process.

3. Regular Maintenance

Regular testing and adjustments are key to maintaining the proper calcium hardness level. Aim to test your water at least once a week, especially during periods of heavy use or high evaporation.

Preventing Problems: Proactive Pool Care

Proactive maintenance is the best way to avoid problems related to calcium levels in your plaster pool. This includes:

Regular water testing: Don't wait for problems to appear before testing. Regular monitoring allows for timely adjustments.
Balancing water chemistry: Maintaining proper pH, alkalinity, and other chemical parameters is crucial for calcium stability.
Regular cleaning: Keeping your pool clean prevents the buildup of contaminants that can interfere with calcium balance.
Professional assistance: Don't hesitate to consult with a qualified pool professional for advice and assistance, especially if you're encountering persistent water chemistry problems.

By understanding the importance of calcium hardness in plaster pools and following these guidelines, you can help ensure the long-term health and beauty of your pool, minimizing the need for costly repairs and maximizing your enjoyment. Remember, prevention is always better than cure.