500gpd membranes to replace 400gpd? And preservative didn’t preserve.

[82cabby]

Hi all-

I just started setting up my ROs for the season and had an unpleasant surprise. There are two RO setups, one with 4- 150gpd membranes and another with 5-400gpd membranes. All were rinsed and stored in pvc with sodium metabisulfite preservative. The 150s did fine and are installed and rinsing right now. The 400s not so much. As soon as I cracked open the tubes I was hit with a really nasty sulfur / sewer smell. No way I’m going to put those back in the system sooooo time for new membranes. My questions are:

A) I see there are 500 gpd that look like they fit the same RO housings. Should I get those instead of the 400? They do cost more.

B) I am assuming that I rinsed the 150s better than the 400s and that’s why there is a difference?

C) I know it’s January not April but looking ahead what is the process for shutting down and storing membranes in preservative? In the past I’ve wrapped them is cling wrap and put them in the fridge but my wife has had enough of that so I tried the preservative and have had issues the last two years.

[Bucket Head]

Years ago, I opened up my storage containers one year and experienced the same smell. I do not know why, I don't know what I did different from the previous season. But since I had nothing to lose, and before I bought new ones, I did a full wash and rinse on them and they looked and smelled good. So I used them and they made good syrup. Maybe mine were not as bad as yours, I don't know, but you could try a cleaning first and then see how they are. Good luck with them.

Steve

[DRoseum]

I previously upgraded my 400 gpds to 500 gpd membranes in a 5 x 500 setup. Worked well.

This year I went to 6 x 600 gpd membranes and added a 2nd pump in parallel to increase flowrate and keep recovery rate and fouling to a minimum. Working great so far.

https://youtu.be/Og9JpgIfE8w?si=yQ98l7YhOxy9laTn

As for cleaning them...always do soap wash first, then flush liberally with permeate, then put them in the perservative. I put mine all in a 5 gallon bucket:
https://youtu.be/W1S3_Zeh8wU?si=KTC4hAGJ7H2dH0to

[Conococheague]

Question- do you store them in a refrigerator? I haven’t had an issue yet (fingers crossed) but I refrigerate them after washing and preserving.

Conococheague

[82cabby]

Question- do you store them in a refrigerator? I haven’t had an issue yet (fingers crossed) but I refrigerate them after washing and preserving.

Conococheague

In the past I’ve wrapped them is cling wrap and put them in the fridge and had good results. But now there are two ROs and 9 membranes and my wife has had enough of that. I switched to the preservative and have had issues the last two years. Obviously other folks have good results so something in my process must be wrong. Watching the video Dan posted was very helpful. I think my wash and rinse was not sufficient. Also I am going to try storing in a 5 gallon bucket instead of the pvc pipes I rigged up. Seems like a better solution.

Last question I promise: should the preservative be run through the RO with the membranes in place to get better saturation throughout the membrane or just really clean the membrane and put it in the bucket full of preservative?

Thanks for the responses gang!

[BAP]

At the end of the season, I wash and rinse my RB25 good. Then run the preservative through the machine recirculating a few minutes to make sure it is well dispersed. Then I cap the 3 liners off with push on caps that I bought. The caps are the same style fitting as the other various fittings on the machine. I don’t remove the membranes. Just store the whole machine in my basement with the preservative solution in it.