Questions on cheap Amazon RO membrane?

[thewire]

What you guys think or have experience on some of the RO membrane they selling? $15 for 2! How's compared to Filmtec?

 

https://www.amazon.com/dp/B0719H4BVL/ref=as_sl_pc_tf_til?tag=&linkCode=w00&linkId=&creativeASIN=B0719H4BVL

[BtmDweller]

Personally, I keep things built for reef keeping, that others have been successful with.  I pay more for better equipment and the highest quality filters to ensure I don't have issues.  I also incorporate other techniques to keep a clean looking tank.  Otherwise with so many factors it's difficult to isolate if a problem occurs, and probably something none of us would think of.  With that said, money is a factor and sometimes experimentation is part of the process.  The chemists and engineers amongst us probably have better feedback for you.  

[Origami]

Typical stabilized salt rejection on this cheaper filter is 97% (96% min.). That's borne out by some of the reviews I just read. On the Dow Filmtec, it's 99% with a minimum of 98%. Under typical circumstances, you can expect your DI resin to last 3x longer with the Filmtec membrane (1% of dissolved salts passing through) versus the cheaper membrane (3% of dissolved salts). Operationally, you'll spend far more on DI resin before you have to change out your membrane. The Filmtec membrane is likely going to be a better choice.