Comparison · under-sink reverse osmosis

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System vs iSpring Water Systems LLC RCC7AK

Certified reductions, five-year cost and fit, for two under-sink reverse osmosis systems.

verified 2026-09-21
sources 11

FilterSpecs verdict

how we score
APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System $0.18 per gallon

6.2 /10

Not scored

iSpring Water Systems LLC RCC7AK

— /10

Not scored

Only APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System holds enough data to score, so this comparison cannot pick a winner on the numbers.

Where they differ

22 of 26 fields

Only the fields where the two systems actually differ. Everything else is identical and sits in the full comparison below.

Table 1 · Differences, plain English
DifferenceAPEC ULTIMATE RO-90 5-Stage Reverse Osmosis SystemiSpring Water Systems LLC RCC7AK
Arsenic removalNSF/ANSI 58 Certified winner Not covered no listing
Barium removalNSF/ANSI 58 Certified winner Not covered no listing
Cadmium removalNSF/ANSI 58 Certified winner Not covered no listing
Chromium-3 (trivalent chromium) removalNSF/ANSI 58 Certified winner Not covered no listing
Chromium-6 (hexavalent chromium) removalNSF/ANSI 58 Certified winner Not covered no listing
Copper removalNSF/ANSI 58 Certified winner Not covered no listing
Fluoride removalNSF/ANSI 58 Certified winner Not covered no listing
Lead removalNSF/ANSI 58 Certified winner Not covered no listing
Radium 226 and 228 combined removalNSF/ANSI 58 Certified winner Not covered no listing
Selenium removalNSF/ANSI 58 Certified winner Not covered no listing
Total dissolved solids removalNSF/ANSI 58 Certified winner Not covered no listing
Turbidity and sediment removalNSF/ANSI 58 Certified winner Not covered no listing
Number of stages 5 Not published
How much it makes a dayDaily production 90 GPD Not published
Adds minerals backRemineralization No Not published
Tells you when to change filtersFilter change indicator manual_timer Not published
Minimum water pressure 40 psi Not published
Maximum water pressure 85 psi Not published
Dimensions 6 x 17 x 18 in Not published
Needs a drain connectionDrain connection Yes Not published
Reversible for renters No Not published
Warranty, parts 1 yr Not published

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Certified reductions compared

NSF · WQA

✓certified a third-party listing exists · ~claimed manufacturer states it, no listing · —not covered no claim made. [5]

Table 2 · Certification status by contaminant
ContaminantAPEC ULTIMATE RO-90 5-Stage Reverse Osmosis SystemiSpring Water Systems LLC RCC7AK
Arsenic ✓Certified NSF/ANSI 58 —Not covered
Barium ✓Certified NSF/ANSI 58 —Not covered
Cadmium ✓Certified NSF/ANSI 58 —Not covered
Chromium-3 (trivalent chromium) ✓Certified NSF/ANSI 58 —Not covered
Chromium-6 (hexavalent chromium) ✓Certified NSF/ANSI 58 —Not covered
Copper ✓Certified NSF/ANSI 58 —Not covered
Fluoride ✓Certified NSF/ANSI 58 —Not covered
Lead ✓Certified NSF/ANSI 58 —Not covered
Radium 226 and 228 combined ✓Certified NSF/ANSI 58 —Not covered
Selenium ✓Certified NSF/ANSI 58 —Not covered
Total dissolved solids ✓Certified NSF/ANSI 58 —Not covered
Turbidity and sediment ✓Certified NSF/ANSI 58 —Not covered

Arsenic

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Barium

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Cadmium

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Chromium-3 (trivalent chromium)

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Chromium-6 (hexavalent chromium)

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Copper

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Fluoride

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Lead

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Radium 226 and 228 combined

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Selenium

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Total dissolved solids

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Turbidity and sediment

APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System ✓Certified NSF/ANSI 58
iSpring Water Systems LLC RCC7AK —Not covered

Cost of ownership

Table 3 · Five years, 700 gallons a year
CostAPEC ULTIMATE RO-90 5-Stage Reverse Osmosis SystemiSpring Water Systems LLC RCC7AK
Purchase priceNot publishedNot published
Filters, 5 years$631.95Not published
Five-year totalNot publishedNot published
Cost per gallon$0.18Not published

Assumes 700 gallons per year. [3]

Full specification comparison

Capacity and water use
SpecificationAPEC ULTIMATE RO-90 5-Stage Reverse Osmosis SystemiSpring Water Systems LLC RCC7AK
TypeUnder-sink reverse osmosisUnder-sink reverse osmosis
Number of stages5Not published
Daily production90 GPDNot published
Filter change indicatormanual_timerNot published
Minimum water pressure40 psiNot published
Maximum water pressure85 psiNot published
Fit and installation
SpecificationAPEC ULTIMATE RO-90 5-Stage Reverse Osmosis SystemiSpring Water Systems LLC RCC7AK
Dimensions6 x 17 x 18 inNot published
Drain connectionYesNot published
Reversible for rentersNoNot published
Water compatibility and warranty
SpecificationAPEC ULTIMATE RO-90 5-Stage Reverse Osmosis SystemiSpring Water Systems LLC RCC7AK
RemineralizationNoNot published
Warranty, parts1 yrNot published

Sources

  1. [1] APEC Water Systems. RO-90 – Ultimate 5-Stage 90 GPD High Output Reverse Osmosis Water Systems for Drinking Water. retrieved 2026-09-20
  2. [2] APEC Water Systems. ULTIMATE RO-90 Installation Instructions & Owner's Manual. retrieved 2026-09-20
  3. [3] The Home Depot. APEC Water Systems Ultimate Premium Quality WQA Certified 90 GPD Under-Sink Reverse Osmosis Drinking Water Filter System RO-90. retrieved 2026-09-20
  4. [4] The Home Depot. APEC Water Systems Ultimate Complete Replacement Filter Set for 90 GPD High Flow 5-Stage Systems FILTER-MAX90. retrieved 2026-09-20
  5. [5] Water Quality Association. WQA Gold Seal certified product listing, APEC Water Systems, NSF/ANSI 58. retrieved 2026-09-20
  6. [6] Water Quality Association. WQA Gold Seal certified product listing, APEC Water Systems, NSF/ANSI/CAN 372. retrieved 2026-09-20
  7. [7] The Home Depot. Model number as listed for APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System. retrieved 2026-09-23
  8. [8] retrieved 2026-09-21
  9. [9] retrieved 2026-09-21
  10. [10] retrieved 2026-09-21
  11. [11] The Home Depot. Model number as listed for iSpring Water Systems LLC RCC7AK. retrieved 2026-09-23
APEC ULTIMATE RO-90 5-Stage Reverse Osmosis System$232.99iSpring Water Systems LLC RCC7AK$234.99