iSpring RCC7 -- the best-value under-sink RO dispenser
The iSpring RCC7 is the most reviewed DIY under-sink RO system in the U.S. market. Five stages: PP sediment (5 micron) + GAC carbon + CTO carbon block + 75 GPD RO membrane + post-carbon polishing filter. NSF 58 certified. The 3.2-gallon pressurized storage tank delivers filtered water through a dedicated chrome faucet at the sink deck at 0.5-1.0 GPM. At 75 GPD membrane capacity, the tank refills in approximately 1 hour after being fully drawn down. For a family of 4 consuming 1-2 gallons of RO water per day, the tank is never depleted between replenishments. Price: $155-220 including all hardware and the chrome dedicated faucet.
iSpring RCS5T -- countertop RO with no installation
The iSpring RCS5T is a 5-stage countertop RO system that connects to the existing kitchen faucet via a diverter valve (included). A 3.2-liter built-in tank and integrated dispense tap deliver filtered water without drilling or under-sink installation. The RCS5T is the appropriate choice for renters, apartments, or households who want RO filtration without permanent installation. Output capacity: approximately 50 GPD. Filter change: sediment and carbon every 6 months, RO membrane every 24 months -- all accessible from the front of the countertop unit without tools.
iSpring RCC7AK -- re-mineralized alkaline RO
The iSpring RCC7AK adds a 6th stage to the RCC7 system: an alkaline re-mineralization filter that adds calcium, magnesium, and potassium back to the RO-purified water, raising pH from approximately 6.5-7.0 (acidic, typical of RO output) to 7.5-8.5 (alkaline). For households who find standard RO water tasteless or who prefer alkaline water for dietary reasons, the RCC7AK provides re-mineralized alkaline water without a separate alkalizer purchase. The alkaline stage filter (iSpring AFC-MN alkaline filter) has a life of approximately 12 months or 1,000 gallons.