AquaSky Water Filters

Aquasky ® ROT-4 Tank is the tank number for a standard tank used on many, many reverse osmosis systems.  Most are systems using standard size replacement filters and reverse osmosis membranes. For help matching up your system see:

Standard Reverse Osmosis systems using standard size replacement filters and RO membranes.

While the tanks in the help file may look different from the Aquasky ROT-4, look to match the described configuration of the filters. The systems shown are using other generic tanks in place of the Aquasky ROT-4.


Easy TDS Membrane Performance Calculator
See If It is Time To Replace Your Membrane

Simply enter your Feed Water TDS and RO Water TDS into the boxes above and click "Submit". The percentage of TDS Rejection will be displayed. We normally recommend membrane replacement once you drop below 75%. This may vary in areas with high TDS in the feed water.

See our selection of TDS meters under Water Tests