iSpring RCC7AK 6-Stage RO vs PUR PLUS FM-3700B — Which Should You Buy?
Side-by-side comparison of iSpring RCC7AK 6-Stage RO and PUR PLUS FM-3700B. We compare specs, performance, and value to help you decide.
Feature Comparison
| Feature | iSpring RCC7AK 6-Stage RO | PUR PLUS FM-3700B |
|---|---|---|
| Type | 6-stage RO | 2-stage carbon |
| Capacity | 75 GPD | 100 gallons |
| Stages | 6 (including alkalinity) | — |
| Removes | Lead, arsenic, fluoride, PFAS | Lead, chlorine |
| Remineralization | Yes | — |
| Tank | 3.2 gallon | — |
| Waste Ratio | 4:1 | — |
| Warranty | 1 year | 90 days |
| Certification | — | NSF |
| Filter Life | — | 3 months |
| Installation | — | Under sink |
| Faucet | — | Included |
iSpring RCC7AK 6-Stage RO
Pros
- ✓99%+ contaminant removal
- ✓6-stage RO
- ✓Remineralization
- ✓Removes fluoride
- ✓Great value
- ✓75 GPD
- ✓Includes tank and faucet
Cons
- ✗Traditional tank design
- ✗4:1 waste ratio
- ✗Slower flow than tankless
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
iSpring RCC7AK 6-Stage RO
The best value RO system—full 6-stage filtration with mineral addition at a mid-range price.
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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