[trapae]

After I’ve gotten several different water reports over the last year and saw how drastically my water changes, I’ve decided to go with a under sink reverse osmosis system. My wife wants one anyway.  After looking through options, looks like APEC Seems to be a pretty good choice for the price and gets TDS really low in general. Was looking at the 50 gallons per day that has the 4 gallon tank.  Does anyone have the system or know about it and have an opinion on it or other systems similar? Thanks in advance.

[mabrungard]

I'm not familiar with APEC, but the most important elements of a RO system is that it employ standard filters and housings such as the 10 or 20 inch housings, and that a high quality RO membrane be used.  Stay away from any system that uses the small or compact filter units or proprietary filter units.  Any of those filters will end up costing you more to operate.

With regard to RO membranes, I've had good performance and longevity in using Filmtec membranes.  Be wary of no-name or unnamed membranes. 

You can learn a lot more about owning and operating a RO system by reading the 2-part articles on RO systems in Zymurgy magazine.  They were written by a highly-experienced engineer that has dealt with water treatment for over 30 years 

[trapae]

Thanks

[MDL]

Also keep in mind you won’t get 4 gallons of water out of the tank at any given time. It will likely provide about half that when “full” and then depending on your incoming water pressure and temperature could take an hour or more to refill the tank again.

You can look for units that have a permeate pump which uses the energy from the brine discharge to pressurize the incoming water feed. They essentially make the unit function as if there is no back pressure from a storage tank. See, as the tank fills and the pressure on the product water side rises, the efficiency begins so to drop off so it takes more and more waste water to make product water. The permeate pump greatly improves the speed of filling the tank. It can result in a slightly elevated TDS of the product water but it negligible in most situations.

Another consideration is what is called a post filter. Many RO for drinking will have a ph neutralizing post filter. This is typically calcite and or magnesium oxide typically called corosex. The post filter will neutralize the slightly acidic product water and also add a small amount of calcium and magnesium back to the water improving the taste by some standards. Pure RO water can be perceived as kind of “flat” tasting. I’ve typically seen ph neutralizing post filters add about 30-50 ppm to the product water. So worth considering if you are going to use the water for brewing.

[mabrungard]

I like the idea of the permeate pump, but I found out through experience, that they are quite loud.  If you want to relive "A tell-tale heart", get the pump.  But if your appreciate your sanity...avoid.

RO water is naturally acidic due to its very low alkalinity and the passage of dissolved gases through the membrane.  Its acidity is not a concern...unless you're going to keep that RO water in contact with any metals.

[MDL]

I like the idea of the permeate pump, but I found out through experience, that they are quite loud.  If you want to relive "A tell-tale heart", get the pump.  But if your appreciate your sanity...avoid.

RO water is naturally acidic due to its very low alkalinity and the passage of dissolved gases through the membrane.  Its acidity is not a concern...unless you're going to keep that RO water in contact with any metals.

Aquatec ERP500 permeate pump is nearly silent. Good for residential RO to 50 gpd. It does make a clicking/thumping sound more so the less full the tank is but I think it’s difficult to hear behind cabinet doors.

[MDL]

I should mention that I’ve had better luck with the noise reduction on the ERP500 when it’s mounted on the RO system itself. When I’ve mounted them to the wall of the cabinet the thumping can transit into the surrounding cabinet and sort of amplify. I could see that being unbearable to live with.

[soymateofeo]

I think you can tee your reservoirs and have a larger tank to fill for your brew water or you can collect 3 ish gallons at a time.

[Buckeye Hydro]

I think you can tee your reservoirs and have a larger tank to fill for your brew water or you can collect 3 ish gallons at a time.

And you can plumb and RO system such that it fills a pressurized tank AND and unpressurized tank.

Russ