Low Chlorine Levels? Easy Fix with Pool FROG^®

If Your Chlorine is Too Low

1. Shock the pool
If the chlorine level is below 0.5 ppm, use a shock treatment.

2. Inspect the Chlorine Bac Pac^®

• The Pac may be empty and need replacement
• Tablets can sometimes stick together and stop dropping into the water as they dissolve. Remove the Pac and shake it firmly so the tablets settle to the bottom
• If your pool has a low flow rate, try priming the Pac by submerging it in the pool until it partially fills with water before placing in the Cycler

3. Adjust the Cycler setting if needed
Only increase the setting if you’re not already at 10 and chlorine remains low:

• Test the chlorine level
• If it is below 1.0 ppm, increase the dial by one setting only
• Retest after 24 hours
• If still low, increase by one more setting
• Repeat until chlorine stays between 0.5–1.0 ppm

4. Check circulation and filtration

• The Bac Pac only dispenses chlorine when the pump is running
• Consider increasing pump run time if it is not already operating continuously
• Clean or backwash the filter regularly to maintain proper water flow

5. Verify back pressure

• The Cycler performs best with 4–8 psi of back pressure
• Low back pressure can prevent enough water from reaching the chlorine tablets
• Installing a smaller return eyeball fitting can help increase back pressure

6. Watch for algae

• Early algae growth can quickly consume chlorine
• Shock the pool, add an algaecide such as FROG^® BAM^®, and brush the pool walls

7. Check for nitrates

• Fertilizers can introduce nitrates, which feed algae and rapidly use up chlorine
• Test water near the return jet. If chlorine is present there but not elsewhere in the pool, nitrates may be the issue
• FROG^® 90-Day Goodbye Phos^® are Pool Pods that help prevent phosphate buildup. Simply drop in the skimmer

8. Verify your test supplies

• Test strips and liquid reagents typically last 12–18 months
• Expired or contaminated test materials can give inaccurate readings
• Avoid handling test strips with wet hands

9. Confirm the correct model was installed

• An in-line infuser installed in an off-line application may not create enough back pressure
• If this has occurred, the unit should be replaced with the correct off-line model