When strips are good enough and when they are not
Use strips for screening, not for high-stakes decisions
- Use strips for screening, not for high-stakes decisions
- FC
- pH
- TA
- CH
- CYA
- Retest with a stronger method before draining, acid washing, or adding a major chlorine dose.
- High sanitizer can bleach some strip pads and make the number look lower than it is.
Strips are fine for a quick check. They are not the final word when you are about to drain water, SLAM a pool, or make a large correction.
- ✕Do not rely on strips alone for SLAM, OCLT, or high-chlorine troubleshooting
- ✕Do not dose from a strip result when the bottle has been open in heat or humidity
- ✕Do not trust a strip color match when the next decision is draining, acid washing, or a large chemical dose
FC / pH / TA / CH / CYA
Use strips for fast trend checks
A strip can answer rough yes/no questions fast.
Verify surprise readings with a liquid kit
Some decisions need better resolution than a color pad can provide.
- Retest with a stronger method before draining, acid washing, or adding a major chlorine dose.
- High sanitizer can bleach some strip pads and make the number look lower than it is.
Distrust strips after heat or humidity exposure
Technique problems make a rough method rougher.
- When the strip is ambiguous, record a range and retest with liquid chemistry.
Never base a major dose on one strip result
Keep strips for screening and move to a liquid kit for real decisions.
Resources (6)
CDC residential pool and hot tub treatment guidance
CDC's baseline note on why strips trail a DPD kit.
Digital Readers and Photometers
A better screen than strips, but still not the final call.
Trust the result before you dose
Retest rules and sample-handling checks before dosing.
Run the test in the right order
The liquid kit when strips are too blunt for the decision.
Pool glossary and core terms
Plain-language help for FC, CYA, and the rest.
Educational guidance only. Verify labels, manuals, local code, and site conditions before acting. Stop for electrical, gas, structural, drain, drowning, injury, emergency, or chemical-mixing risk.