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Read ArticleDI Resin Calculator: Calculate Your System Capacity
Calculate exactly how much deionized water your system can produce before resin replacement. Get instant results based on your water quality and system specifications.
DI Resin Calculator
* Enter your exact values for precise calculations
Your Precise Results
Based on your exact parameters
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Total Gallons
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Output
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Estimated Life
Configuration:
Recommendation:
*Results based on industry-standard calculations and your specific parameters.
How This Calculator Works
Understand the science behind our accurate calculations
Industry Standards
Our calculator uses proven industry formulas based on ion exchange capacity and your specific water conditions to provide accurate estimates.
Proven Formula
Our formula uses industry standard grain-gallons per cubic foot measurement to deliver accurate, real-world estimates for your unique water conditions.
Cost Analysis
We calculate costs using average resin prices: ~$200/cu ft for budget resin, $310 for standard quality, and ~$400 for premium commercial-grade resin.
Pro Tips for Maximum Efficiency
Extend Your Resin Life
Pre-treatment matters: Using a water softener before your DI system can double or triple your resin life by removing calcium and magnesium.
Monitor regularly: Check your output TDS daily. Replace resin when it consistently reads above 10 ppm.
Proper flow rate: Keep flow rates below 2 GPM per cubic foot for optimal ion exchange.
Water Quality Variations
Seasonal changes: TDS can vary by 20-30% seasonally. Test monthly and adjust calculations.
Well water: If using well water, test for iron and silica - these can significantly reduce resin life.
Ready to Get Started with DI Water?
Find the perfect deionization system for your needs. Our experts can help you choose the right setup based on your water quality and application requirements.
Frequently Asked Questions
Get answers to common questions about DI resin calculations and deionized water systems
How accurate is this calculator?
Our calculator provides estimates within 10-15% accuracy based on standard ion exchange rates. Actual results may vary based on water chemistry, temperature, and flow rates. For best results, monitor your actual TDS output and adjust accordingly.
What TDS level should I aim for in my DI water output?
For most applications, aim for 0-10 ppm TDS. Laboratory use may require 0-1 ppm, while car washing and window cleaning work well at 0-20 ppm. Replace resin when output exceeds your application's requirements.
Can I regenerate my DI resin instead of replacing it?
Mixed bed DI resin typically cannot be regenerated on-site. However, some companies offer resin exchange services where they regenerate your exhausted resin off-site, which can reduce costs by 30-40%. Separate bed systems can be regenerated on-site.
How do I know my resin capacity?
Check your system documentation or measure your tank dimensions. A standard 10" x 44" tank holds approximately 1.5 cubic feet, while a 14" x 65" tank holds about 4.5 cubic feet of resin.
How long does DI resin last?
DI resin lifespan depends on your water's TDS level and usage volume. With 200 ppm water, 1 cubic foot of resin typically produces 100-150 gallons. Higher TDS water reduces capacity, while lower TDS extends it. Most users replace resin every 2-8 weeks.
What is the difference between DI and RO water?
DI (deionized) water uses ion exchange resins to remove dissolved minerals, achieving 0-10 ppm TDS. RO (reverse osmosis) uses membranes to filter contaminants, typically achieving 10-50 ppm TDS. DI is better for spot-free applications, while RO is more economical for large volumes. Many systems combine both for optimal results.
How much does DI resin cost?
DI resin costs vary by quality and quantity. Budget mixed-bed resin costs $150-200 per cubic foot, standard quality runs $250-350, and high quality premium resin costs $350-450. Bulk purchases reduce costs. Calculate your cost per gallon using this calculator to determine if DI water is economical for your application.
When should I replace my DI resin?
Replace DI resin when your TDS meter reads above your acceptable threshold (typically 10-20 ppm). Color-changing resin shifts from blue/amber to green/clear when exhausted. Without monitoring, replace when you notice water spots, longer drying times, or mineral deposits returning.
What size DI system do I need?
System size depends on your daily usage and water quality. For home use (1-5 gallons/day), a 0.5-1 cubic foot system works well. Small businesses (10-50 gallons/day) need 1-3 cubic feet. Commercial operations (100+ gallons/day) require 3-10 cubic feet or larger. Use this calculator to determine your exact needs.
Can I use DI water for drinking?
DI water is not recommended for drinking as it lacks essential minerals and can be aggressive to plumbing and your body. It's ideal for applications requiring pure water like car washing, window cleaning, laboratories, aquariums, and manufacturing. For drinking, consider a standard RO system that retains some beneficial minerals.
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