Verdict
Head-to-head · Best Under-Sink Water Filters

APEC Water ROES-PH75 Essence Alkaline Reverse Osmosis System vs Cloud RO Under-Sink Reverse Osmosis System

Which is the better buy? Side-by-side on rating, price, strengths, and watch-outs — with the published ratings we averaged to get there.

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The short answer

Cloud RO Under-Sink Reverse Osmosis System comes out ahead by a narrow margin (4.4 vs 4.3). Cloud RO Under-Sink Reverse Osmosis System is best for: households that want app-monitored reverse osmosis water without an under-sink outlet. Read the strengths below before deciding.

APEC Water ROES-PH75 Essence Alkaline Reverse Osmosis System
Ranked #3 in Best Under-Sink Water Filters
APEC Water ROES-PH75 Essence Alkaline Reverse Osmosis System
1 source$190as of Oct 17

The APEC ROES-PH75 is a six-stage, tank-based under-sink reverse osmosis system rated at 75 gallons per day, with a 4-gallon tank, a dedicated chrome faucet and a final calcite remineralisation stage. Water Filter Guru scored it 8.87/10 after lab testing showed it removed every contaminant found above health guideline levels and cut dissolved solids by 93%, though its measured output and water efficiency were well short of APEC's figures. Bob Vila named it best overall, with its tester reporting clearer, better-tasting water from the first day in a home on hard municipal water. It suits households that want thorough, low-cost purification and have cabinet space to spare; anyone short on under-sink room, or keen to limit wastewater, should look at a tankless or pumped system instead.

Strengths
  • — Removed every contaminant detected above health guideline levels in Water Filter Guru's lab test
  • — Cut total dissolved solids by 93%, from 875 to 54 ppm, with no significant TDS creep
  • — Calcite remineralisation stage kept the filtered water from turning acidic
Watch-outs
  • — Wasteful without a pump: 10.6 oz sent to drain per 1 oz purified on a small draw
  • — Installation took 90 minutes and needs a dedicated faucet hole drilled in the countertop
  • — The 4-gallon storage tank fills much of the under-sink cabinet
Cloud RO Under-Sink Reverse Osmosis System
Higher ratedRanked #2 in Best Under-Sink Water Filters
Cloud RO Under-Sink Reverse Osmosis System
2 sourcesall derived

The Cloud RO is a battery-powered, app-connected under-sink reverse osmosis system with eight filtration stages, remineralisation, a 2.8-gallon tank and a rated 80 gallons per day. The Spruce named it its best smart system after a year of use, citing easy setup, useful app monitoring and alerts, and enough output for a large household; Good Housekeeping found it compact, quiet and noticeably better tasting than NYC tap water. Both flag the cost: Good Housekeeping puts the starting price at about $600 with $200 replacement filters, and The Spruce notes a 1:1 waste ratio. It suits households that want RO water with real-time monitoring; buyers on a budget or short of cabinet space should look elsewhere.

Strengths
  • — The Spruce found setup easy, with well-labelled lines and fittings
  • — App shows tap and filtered water quality and sends filter-change alerts
  • — Battery powered, so no outlet is needed under the sink
Watch-outs
  • — Costs more than many RO systems, and replacement filters cost about $200
  • — 1:1 waste ratio, more wasteful than The Spruce's top iSpring pick
  • — Included faucet feels a little flimsy, and flow sputters on first use each day

Derived means the reviewer published no score, so one was inferred from their written verdict. Everything else is a number the publisher printed. How we rank.

How they stack up

APEC Water ROES-PH75 Essence Alkaline Reverse Osmosis System

The ROES-PH75 is a reverse osmosis system, unlike the Clearly Filtered 3-Stage Under the Sink, which reduces contaminants without RO, and the Aquasana Claryum AQ-5300+, which is a no-wait filter that keeps healthy minerals. The APEC instead strips most minerals and adds a calcite stage at the end, and it needs a 4-gallon storage tank and a drain connection that sends water to waste.

Cloud RO Under-Sink Reverse Osmosis System

Unlike the Waterdrop G3P800 Tankless Reverse Osmosis System, the Cloud RO stores water in a 2.8-gallon tank and runs on a battery rather than mains power. Like the APEC Water ROES-PH75 Essence Alkaline system it adds minerals back after RO filtration, but it is priced from about $600 and adds app monitoring; the Aquasana Claryum AQ-5300+ is a non-RO filter for buyers who want to avoid a tank altogether.

Specs side-by-side

SpecAPEC Water ROES-PH75 Essence Alkaline Reverse Osmosis SystemCloud RO Under-Sink Reverse Osmosis System
Filtration Stages6 (sediment, 2 carbon blocks, RO membrane, carbon post-filter, calcite remineralisation)8
Rated Output75 gallons per day—
Storage Tank4 gallons—
Dimensions15.5 x 5.25 x 17.5 in11 x 7 x 16 inches
CertificationsNSF/ANSI 58 (TDS reduction), lead-free design—
Power SourceWater pressure (no pump)—
Warranty1 year limited—
Type—Under-sink reverse osmosis with tank
Daily Production Rate—80 gpd
Tank Capacity—2.8 gallons
Power—Battery
Waste Ratio—1:1
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