
APEC Ultimate RO-90
Score: 85/100
Express Water Alkaline RO
Score: 78/100Rankings

The APEC Water Systems RO-90 Ultimate Series is a WQA-certified, 5-stage under-sink reverse osmosis filtration system designed to produce 90 gallons of ultra-pure water per day. It features a durable metal frame, US-made filters with extended lifespan, and a 4-gallon storage tank to support households of four or more people. It is ideal for daily drinking and cooking in areas with high contaminants like lead, arsenic, or fluoride.

The Express Water 10-Stage RO System is a comprehensive under-sink filtration solution with alkaline remineralization and NSF 58 certification. It includes a 4-gallon tank to compensate for its slow flow rate, making it suitable for families. However, it requires adequate cabinet space and sufficient water pressure to operate effectively.
| Attribute | ![]() | ![]() |
|---|---|---|
5 stages | 10 stagesbest | |
90 gallons per day | 100 gallons per daybest | |
100 percentbest | — | |
4 gallonsbest | 4 gallonsbest | |
— | 7 countbest | |
12 monthsbest | 6 months | |
| ↓ lower better | 5.25 inches | 5 inchesbest |
| ↓ lower better | 17.5 inches | 17 inchesbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Compliance & Safety(1) | ||
Certifications | WQA Gold Seal | NSF 58 |
Maintenance(1) | ||
Filter Lifespan (months) | 12 months | 6 months |
Design(2) | ||
System Width (inches) | 5.25 inches | 5 inches |
System Height (inches) | 17.5 inches | 17 inches |
Performance(4) | ||
Filtration Stages (stages) | 5 stages | 10 stages |
Daily Production Rate (gallons per day) | 90 gallons per day | 100 gallons per day |
Contaminants Removed (count) | null count | 7 count |
Feed Water Pressure (PSI) | 50 PSI | 40-80 PSI |
Features(1) | ||
Remineralization | false | true |

Products in the top-left offer the best value (high score, low price).

Professional reviewers from sources like Lowe's and Home Depot highlight the RO-90's premium quality, WQA certification, and superior contaminant removal capabilities. They praise the durable metal construction, eco-friendly design, and the longevity of US-made filters, positioning the system as virtually maintenance-free with a crisp taste that outperforms bottled water.
Everyday users consistently praise the excellent water quality and taste, noting significant reductions in Total Dissolved Solids (TDS). Common themes include satisfaction with the easy installation process, the long lifespan of the filters, and the overall value for obtaining pure water for growing families.



Professional assessment highlights the Express Water system as a certified, comprehensive solution for residential drinking water, emphasizing the NSF 58 certification.
The product is marketed as a practical solution for families and well water users, with the 4-gallon tank specifically noted as addressing the slow flow rate.
