Formulating Optimal Car Wash Chemistry:  How Water Quality Affects Your Chemical Program

by Howco, Inc.

Selecting the right car wash chemicals is a balance of effectiveness, safety, and cost. However, an important determining factor is often overlooked:  water quality. The minerals, pH level, and total dissolved solids (TDS) in your water directly influence how well your chemicals perform, how efficiently your equipment operates, and the quality of the final wash. To build a high-performing chemistry program, we must first examine the water feeding it and adjust for the needs of your wash type. 

1. Match Your Chemicals to Your Wash Type 

Different car wash systems require different chemical strategies: 

• <strong>Automatic Washes (In-Bay and Tunnel/Conveyor Systems):</strong> Benefit from high-foaming, fast-acting detergents and specialized drying agents designed for quick cycles. 

• <strong>Self-Serve Washes:</strong> Need durable, versatile products that work well with variable water conditions and manual application. 

Choosing chemicals that complement your equipment ensures consistent cleaning and efficient operation. 

2. Understand pH Balance and Chemical Effectiveness 

All cleaners—from alkaline presoaks to acidic wheel cleaners—must align with both your water profile and your cleaning goals. 

• <strong>Alkaline Cleaners:</strong> Great for grease, dirt, and road film. 

• <strong>Acidic Cleaners:</strong> Used for targeted jobs like removing mineral deposits or brake dust. 

• <strong>Neutral Cleaners:</strong> Safe for frequent use and protective finishes like waxes and ceramic coatings. 

The rule of thumb: use the mildest effective product to protect vehicles, equipment, employees, and the environment. 

3. Water Quality: The Foundation of a Good Chemistry Program 

Water hardness, pH, and mineral content can vary widely, even among locations in the same city. These factors dramatically influence wash results. 

Soft vs. Hard Water 

• <strong>Soft Water Improves Performance:</strong> Without calcium and magnesium to interfere, detergents foam better, clean deeper, rinse more easily, and require less product, saving money while enhancing results. 

• <strong>Hard Water Creates Challenges:</strong> Soaps bind to minerals instead of dirt, reducing cleaning power and increasing chemical usage. It also leaves spotting, dulls paint, clogs nozzles, and promotes scale buildup, raising maintenance costs. 

Because hard water is common in both municipal and well systems, operators must evaluate each wash individually. 

The Role of pH and TDS 

• <strong>Extreme pH levels</strong> can cause corrosion, toxicity, and equipment wear. 

• <strong>High TDS levels (total dissolved solids)</strong> contribute to spotting and can overwhelm filtration systems. A <strong>Reverse Osmosis (RO)</strong> or <strong>Deionized (DI)</strong> system may be necessary for a spotless final rinse. 

4. Prioritize Safety and Environmental Responsibility 

As environmental regulations tighten, choosing safer, greener solutions is increasingly important. 

• Look for <strong>biodegradable, eco-friendly options</strong>. 

• Always review <strong>Safety Data Sheets (SDS)</strong> for proper handling and PPE requirements. 

A safer chemical program protects your employees, customers, and community. 

5. Test, Adjust, and Optimize 

The most effective chemical program is built on testing and data, not guesswork. Howco conducts complimentary on-site water testing, including pH and TDS measurements, and works with professional labs and equipment manufacturers to evaluate each location’s water profile. 

With these insights, we help operators: 

• Choose the right detergents, presoaks, protectants, and drying agents 

• Determine ideal dilution ratios 

• Address hardness, pH, or TDS challenges 

• Determine the need for water softener, and if so, the proper amount 

• Reduce cost per wash 

• Maximize equipment lifespan 

• Achieve consistent, high-quality wash results 

The better you understand your water quality and how it interacts with your chemicals, the easier it becomes to develop a cost-effective, efficient, and environmentally conscious wash program. With the right chemistry—and the right water—operators can achieve superior cleaning results and long-term Car Wash Success®. 

Contact Howco to schedule an on-site water analysis and build a personalized chemistry program tailored to your car wash.