Most reliable RO membranes

[jdieck]

<a href=showthread.php?s=&postid=9658577#post9658577 target=_blank>Originally posted</a> by Justdrew
I think the Filmtec 75 gpd is the 2nd best choice to a Spectrapure Select. Drew

A 75 Filmtec and a Spectrapure Select are exactly the same membranes, from the same manufacturer (dow) made under the same specifications and materials, the only difference is that the Spectrapure is tested to give you and additional 1 to 0.5% rejection points and will cost $100.00 rather than $40.00
In my opinion the difference in cost does not worth the certainty that you will get a little more rejection. If is not select there is still 50/50 you will get it anyhow. (disclaimer: I use the select ). I wonder what does Spectra does with the ones they found with slightly lower rejection. Will they sell them for less than $40.00?

 

[AZDesertRat]

Not all select series are Dows, the new 150 GPD are not. The testing is not the only difference, all Selects are kept wet in a proprietary solution which Charles says increases the membranes efficiency. The ones that do not meet select standards are sold for less demanding uses.

 

[jdieck]

<a href=showthread.php?s=&postid=9659371#post9659371 target=_blank>Originally posted</a> by AZDesertRat
The ones that do not meet select standards are sold for less demanding uses.

So if I buy a non select from Spectra I will know it is lower rejection but if I buy from someone else I'll be 50/50 chance.

 

[AZDesertRat]

Lower rejection from Spectrapure is usually still in the 96+ % range, just not 98+%. My 90 GPD is averaging 99.25% for its 8 months of use so far. I just bought a 150 GPD but have not had the chance to install it yet. I plan to run in by itself for some testing then piggyback it with the 90 for a 240 GPD system.