Aquasana AQ-5200 vs PUR PLUS FM-3700B — Which Should You Buy?
Side-by-side comparison of Aquasana AQ-5200 and PUR PLUS FM-3700B. We compare specs, performance, and value to help you decide.
Feature Comparison
| Feature | Aquasana AQ-5200 | PUR PLUS FM-3700B |
|---|---|---|
| Type | Carbon block | 2-stage carbon |
| Certification | NSF | NSF |
| Removes | Lead, PFOA, PFOS, microplastics | Lead, chlorine |
| Capacity | 500 gallons | 100 gallons |
| Filter Life | 6 months | 3 months |
| Electricity | None | — |
| Installation | Under sink | Under sink |
| Warranty | 1 year | 90 days |
| Faucet | — | Included |
Aquasana AQ-5200
Pros
- ✓NSF certified
- ✓Removes lead, PFOA, PFOS
- ✓No electricity
- ✓No tank
- ✓Easy installation
- ✓Affordable
- ✓Good flow rate
Cons
- ✗Not RO
- ✗Filter replacements ~$60
- ✗Doesn't remove fluoride
PUR PLUS FM-3700B
Pros
- ✓Budget-friendly
- ✓NSF certified
- ✓Reduces lead, chlorine
- ✓2-stage
- ✓Simple install
- ✓Dedicated faucet
- ✓Trusted brand
Cons
- ✗Basic filtration
- ✗Doesn't remove fluoride
- ✗Filter life 3 months
Our Verdict
Aquasana AQ-5200
The best value under-sink filter—NSF-certified contaminant removal without the cost of RO.
Special Deal Available — See OfferPUR PLUS FM-3700B
The best budget under-sink filter—basic NSF-certified filtration at the lowest price.
Limited Offer — Check Today's PriceOur Methodology
We test each under-sink filter for contaminant reduction, installation ease, and long-term cost. No manufacturer has editorial influence.
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