How much does it cost to acid wash an Ottawa pool that has severe calcium buildup?

Acid washing a concrete or gunite pool with severe calcium buildup typically costs $800 to $1,500 in Ottawa, depending on pool size and the severity of the calcium deposits. This process involves draining the pool completely and applying muriatic acid to dissolve the calcium scale and restore the pool surface to a clean, smooth finish.

Ottawa's hard water contributes significantly to calcium buildup problems. The city's water supply contains elevated levels of calcium and magnesium, and when combined with high pH levels and warm summer temperatures, calcium carbonate readily precipitates out of solution and bonds to pool surfaces. This is particularly problematic for concrete and gunite pools, where the porous surface provides plenty of texture for calcium to adhere to. The buildup appears as white, chalky deposits that feel rough to the touch and can harbor algae and bacteria.

The acid washing process requires draining the pool completely, which should only be done during Ottawa's warmer months (late May through early September) to prevent freeze damage to the empty shell. A professional will apply diluted muriatic acid using brushes and specialized equipment, working in small sections to dissolve the calcium deposits without damaging the underlying concrete. The process typically takes 1 to 2 days depending on pool size and requires proper neutralization and disposal of the acidic wastewater according to environmental regulations.

Important considerations for Ottawa pool owners: Acid washing removes a thin layer of the pool surface along with the calcium deposits, so it should only be done when necessary - typically every 5 to 7 years for pools with moderate calcium issues, or every 3 to 5 years for pools with severe hard water problems. The process temporarily makes the pool surface more porous, so immediate replastering may be recommended for severely etched surfaces, adding $8,000 to $15,000 to the total cost. Never attempt acid washing as a DIY project - muriatic acid is extremely dangerous and requires professional handling, proper ventilation, and specialized safety equipment.

Prevention is far more cost-effective than repeated acid washing. Maintaining proper water chemistry (pH between 7.2 and 7.6, total alkalinity 80-120 ppm) and using a quality sequestering agent can significantly reduce calcium buildup. If you're dealing with severe calcium deposits, you can connect with experienced pool service professionals through the Ottawa Construction Network directory who specialize in acid washing and calcium remediation.