time for new RO?

[BigJim]

I was wondering how to tell if it is time to replace my RO in my RO/DI water filter? My TDS meter reads 180 before the RO and 55 after the RO. I have a 75gpd RO filter on the unit. Here are some other specs if needed.

Water prior to RO/DI 195
after 3 pre filters 175 (new filters)
after RO 55
after DI 0 (new DI)

Thanks in advance:rollface:

[atvdave]

Looks like your only getting about a 70% rejection rate. For the Dow 75GPD membranes you should be getting close to 98%.

Cold water temp does effect the out put of most membranes but I don't think by that much.

I say it's time to replace.

At 55 TDS your DI resin won't last long.

[BigJim]

The DI is getting exhausted faster than usual. Where is the cheapest place to buy a new membrane. I can't remember where I got the one I have. Which is better 75gpd or 100gpd? From what I remember, the 75gpd has a higher rejection rate. My unit came originally with the 100 but I quickly switched to the 75 but this was a few years ago.

[atvdave]

The 75 is the better one. 75GPD is 98%, the 100GPD is 90%.



http://www.thefilterguys.biz/

http://www.buckeyefieldsupply.com/

http://www.spectrapure.com/

http://www.purelyh2o.com/

http://www.airwaterice.com/

http://www.melevsreef.com/