Before choosing, installing, or troubleshooting any water filter, it helps to understand what you should actually test for. Different filtration devices target different contaminants, so the testing priorities shift depending on whether you’re dealing with drinking water, shower water, pitcher filters, or whole-house systems.
Below are five universal testing categories, followed by how they apply to each filtration type.
The 5 Key Water-Testing Categories
- Basic Water Chemistry
pH, hardness, alkalinity, total dissolved solids (TDS), conductivity. - Aesthetic Parameters
Chlorine/chloramine, turbidity, iron, manganese, odor-causing compounds. - Health-Related Contaminants
Lead, copper, arsenic, nitrates/nitrites, fluoride (optional), heavy metals, VOCs. - Microbiological Safety
Total coliforms, E. coli, heterotrophic plate count (HPC) if needed. - System-Specific or Source-Specific Issues
This includes well-water factors (sulfur, tannins), disinfection byproducts (THMs), hardness scaling potential, or anything known to be elevated in your region.
How These 5 Testing Categories Apply to Each Filter Type
1. Drinking Water Filters (Under-Sink, Countertop, RO, etc.)
1. Basic Water Chemistry
Measure pH, hardness, and TDS to ensure the filter is operating within its design limits. High hardness can reduce RO efficiency.
2. Aesthetic Parameters
Chlorine/chloramine testing is crucial — many drinking filters rely on activated carbon, which has finite capacity.
3. Health-Related Contaminants
Lead, copper, arsenic, nitrate, VOCs, PFAS.
This category matters most for drinking water because ingestion is the primary exposure route.
4. Microbiological Safety
Only necessary if you’re on well water or after a boil-water advisory. Most point-of-use systems don’t treat microbes unless they include UV or ultrafiltration.
5. System-Specific
For RO systems: test for TDS rejection (input vs. output).
For carbon systems: test for breakthrough of chlorine/VOCs.
2. Shower Filters
1. Basic Water Chemistry
Chlorine and chloramine reduction are the main performance indicators. These must be measured chemically—not with a TDS meter, which cannot detect chlorine at all. To verify performance, test chlorine levels pre- and post-filter specifically under hot-water conditions, since hot water accelerates chlorine off-gassing and affects media efficiency.
2. Aesthetic Parameters
Chlorine and chloramine reduction are the primary targets. Test pre- and post-filter to evaluate real performance in hot water.
3. Health-Related Contaminants
Metals testing is less critical unless you have deteriorating plumbing. KDF media can reduce some metals, but effectiveness varies.
4. Microbiological Safety
Testing is only relevant if using private well water or if the system is prone to stagnation. Shower filters are not microbiological purifiers.
5. System-Specific
Temperature-dependent testing: many media (especially carbon) lose significant effectiveness in hot water. Evaluate hot-water conditions specifically.
3. Water Filter Pitchers
1. Basic Water Chemistry
TDS and hardness help you understand pitcher lifespan and flow rate degradation.
2. Aesthetic Parameters
Chlorine, taste, odor compounds. Pitchers are primarily designed for this category.
3. Health-Related Contaminants
Lead, copper, mercury, and sometimes PFAS depending on the cartridge. Testing is useful around cartridge-change intervals.
4. Microbiological Safety
Pitchers do not disinfect water. Only test microbes if using untreated water (not recommended).
5. System-Specific
Flow-rate testing and cartridge saturation testing to detect performance drop-off.
4. Whole-House Filtration Systems
1. Basic Water Chemistry
Hardness, pH, alkalinity — all essential for choosing the right pre-filters and media.
High hardness or low pH can damage plumbing or reduce system lifespan.
2. Aesthetic Parameters
Iron, manganese, hydrogen sulfide, turbidity—major factors for whole-house setups, especially on well water.
3. Health-Related Contaminants
Testing for lead, arsenic, nitrates, VOCs, PFAS depends on your source water.
Whole-house filters typically address aesthetic issues; drinking-water risks must still be managed at point-of-use.
4. Microbiological Safety
Important for wells or systems with storage tanks. Consider total coliforms and E. coli testing.
5. System-Specific
Flow rate, pressure drop, and media exhaustion are critical.
Test pre- and post-system to identify which stage is degrading.
Summary Table
| Filter Type | Basic Chemistry | Aesthetic | Health-Related | Microbial | System-Specific |
|---|---|---|---|---|---|
| Drinking water filters | pH, hardness, TDS | Chlorine | Lead, arsenic, nitrates, PFAS | Optional | RO rejection, carbon breakthrough |
| Shower filters | Hardness | Chlorine/chloramine | Metals (limited) | No | Hot-water performance |
| Pitchers | TDS, hardness | Chlorine, taste | Lead, mercury | No | Cartridge saturation |
| Whole-house systems | Hardness, pH | Iron, turbidity | Region-specific | Important for wells | Pressure, media exhaustion |
EASYTEST 7-Way Pool Test Strips, 150 Strips Water Chemical Testing for Hot tub and Spa
Summary
AFFORDABLE 150 STRIPS: This water chemical testing kit contains 150 test strips. Enough balanced for your swimming pool, hot tub, spa and other water testing. At least testing twice a week is recommended to keep your pool sparkling clean and safe.