Filling Your Pool with Well Water

Well Capacity Considerations

Pool Sizes

Filling Time

Formula: Gallons ÷ GPM ÷ 60 = Hours

• 5 GPM well: 50 hours for 15,000 gallons
• 10 GPM well: 25 hours for 15,000 gallons
• 20 GPM well: 12.5 hours for 15,000 gallons

Don't Run Well Dry

• Well has limited recovery rate
• Continuous pumping can outpace recovery
• Running dry damages pump
• May stir up sediment

Safe Filling Strategy

• Fill in sessions (4-6 hours at a time)
• Let well recover between sessions
• Monitor for air sputtering (sign of low water)
• Plan for 2-4 days to fill

Water Quality Issues

Iron

• The biggest issue
• Chlorine oxidizes iron
• Pool turns green, brown, or rust
• Stains pool surfaces

Solution

• Add metal sequestrant BEFORE chlorine
• Follow product instructions
• May need multiple treatments
• Or filter through hose attachment

Copper

• Turns hair green
• Blue-green staining
• Treat same as iron

Hardness

• Well water often hard
• Can cause scaling
• May need to add acid
• Test and balance

pH

• Well water pH varies
• Pool needs 7.2-7.6
• Adjust after filling

Bacteria

• Pool chlorine will kill
• Not typically a concern

Filling Tips

Before Filling

• Test well water for iron, copper
• Know your well's GPM/recovery
• Buy metal sequestrant if needed
• Have pool chemicals ready

During Filling

• Fill in sessions, not continuously
• 4-6 hours on, 4-6 hours recovery
• Monitor household water (may have lower pressure)
• Watch for pump issues

After Filling

• Add metal sequestrant first (if iron present)
• Wait per product instructions
• Then add chlorine/shock
• Balance pH, alkalinity, hardness
• Run filter continuously

Hose Filter Option

• Attach-on filters remove some metals
• Reduces but may not eliminate
• Worth using if iron is moderate

Common Problems

Pool Turned Green/Brown

• Iron oxidized by chlorine
• Add metal sequestrant
• Run filter continuously
• May need to vacuum to waste

Staining on Pool Surface

• Metal deposits
• Use stain remover
• Scrub affected areas
• Keep metals sequestered

Ran Well Dry

• Stop filling immediately
• Let well recover (several hours)
• Check pump operation
• May have stirred sediment

Pump Overheated

• Running too long continuously
• Let pump cool
• Fill in shorter sessions

Alternatives

Water Delivery

• Tanker truck fills pool
• Fast (few hours)
• No well stress
• Cost: $200-$500+ depending on size

Hybrid Approach

• Partial well water
• Partial delivered water
• Dilutes any iron issues
• Reduces cost vs full delivery

Fire Hydrant

• Some areas allow with permit
• Metered use
• Fast fill
• Check with water district

We service all major pump brands including Franklin Electric, Grundfos, Goulds (Xylem), and Sta-Rite (Pentair). Our trucks carry common parts and components for same-day repairs.

Frequently Asked Questions

Can I fill my pool with well water?

Yes, but don't run well dry. Fill in sessions. Watch for iron turning water green. Treat with sequestrant.

Will well water turn my pool green?

If iron is present, yes—when chlorine is added. Use metal sequestrant before chlorine to prevent.

How long to fill a pool from a well?

Depends on GPM. At 10 GPM, 15,000 gallons = 25 hours. Spread over several days for well recovery.

Will filling my pool damage my well?

Not if you're careful. Don't run continuously—let well recover. Don't run pump dry.

Is it cheaper to fill with well water?

Yes—just electricity cost. Water delivery is $200-$500. But consider time and potential issues.