Anaerobic smell from RODI
 

I own a Spectrapure RODI system for about a year now. Recently, I smell rotten eggs from the waste water line when the system started to make water.

The anaerobic smells only lasted about 10sec from the waste water line when the unit start making water. After the initial 10secs, everything goes back to normal.

Other than that, my system is still showing the TDS that i normally have.

I sent an email to Spectrapure, and they were saying that it probably comes from Anaerobic bacteria in the membrance and it does not affect water quality. They suggest to do a fast flush on the membrance. Unfortunately, I do not have a fast flush kit and I don't intend to purchase one if it is not necessary

So, should I just leave it??? Any thoughts??

A flush "kit" is easy to make if you can figure out where the flow-restrictor is located. It is typically at a connection fitting somewhere in the waste line. To make a flush you insert a "T" fitting before and after the flow-restrictor. This forms a half loop that bypasses the flow-restrictor. You then place a shut-off valve in that half loop. When you open the valve the waste water travels though the loop and around the flow-restrictor . Without any restriction it flows freely and flushes the line and the membrane. After flushing for a couple of minutes you just shut the valve and it returns to normal function.

Allen

Have you ever disinfected the filter housings? Does the unit sit for extended periods of time without use? Is it mounted in a protected place away from heat and direct lighting?

Do you mean the Membrance housing? I did not disinfected the housing. Everytime when I change the pre-filter/Carbon block/DI, I just rinse the housing with warm water and then use a napkin to dry it.

I use my RO/DI every other day and make about 50g/week. It is in frequent use and is not under direct light.

You should disinfect all housings at least once a year and every 6 months at filter change time is better. Its an easy process and only takes a little time. Remove all the filters including the membrane, put 2 tablespoons of unscented bleach in the first housing and run it through until its gone. Reinstall all filters and its done. Bacteria can and will grow inside the housings and on the membrane as you have removed any residual chlorine with the carbon so are unprotected past that point.

When you said until it is gone, you mean until you can't smell any bleach??

Any particular brand of bleach to use on the safe side??

Yes. Its best to let it run for 15-20 minutes to be safe. Any unscented bleach is OK, I use Clorox just because thats what the boss buys!

Do you smell the rotten egg oder (hydrogen sulfide) from your tap water?

Russ @ BFS

No, I tried that and the Tap water is fine.

So, yesterday, I opened up the RO housing and sure enough, I saw Red Slime at both end of the Membrance. There are some at the John G fitting that I could not get to. So to be quick, this is what I did. I told out the RO Membrance and Rinse it under RO water and gently brush off the Red slime bacteria on both side. Then without the Membrance, i took the housing and run it under tap water and give a hard brush as much as i can. Then I put everything back.

Due to time, i did not use the Bleach method, but I am planning to do so in a few weeks time.

The red slime is bacterial, and also likely is within the membrane. Time for a new membrane. "Biofouling" is the jargon.

Remember you have no chlorine downstream of the membrane.

How old is the membrane?

Is it performing poorly?

If you look back in my RO posts you will find I have brought up this very issue time and again. Regular maintenance is a must with RO systems, you can't just install it and forget it. Regular filter changes, disinfection of the components and protecting the unit from heat and light is very important. Glad you found it!

Yes, the RO efficiency is going down. I used to get RO out TDS = 2. Now I am getting RO out TDS = 15. Should I continue to use it??

It is only one year old.

Not sure I understand the light. The Membrane housing is Opaque, so there should be any light entering the housing??

Are the prefilter and carbon housings opaque? I actually prefer opaque housings for all filters myself for two reasons, one is they do not allow light in and two they are constructed of a stronger more resilient plastic. Once bacteria takes hold its tough to get rid of unless you tear everything down, disinfect all components and install all new filters including the membrane.

I would say it is to late for your membrane as it is fouled beyond repair. What you see on the outside has also contaminated the interior of the membrane. Since you have red slime you will have to use great care in disinfecting you housings. You should also replace all of your other filters as they more then likely are fouled also.

Jim

IR - I've sent you instructions to sanitize the system - that would be a good place to start.

Russ @ BFS

Thx all

Argghh.....I just add a Maxcap and Replace my DI. I got to throw it away?? The TDS coming out of the Maxcap and DI is still TDS=0. Can i wait until it started to creep up?

Some of the John G fitting is hard to get to and I am not sure I can brush it off. So, with Bleach sanitizing the whole system, is it guaranteed that the Red Slime will be 100% gone??

Also, my pre-filter and the Carbon block should be protected by the Chlorine right?

One more question. When Sanitizing the unit, do I need to remove the Auto-shutoff valve?

Someone told me that I can use Hydrogen Peroxide to soak the membrance for 30mins to kill the bacteria. I probably going to try that.

The DI is probably innoculated with the bacteria. Sorry fella...

Sorry but I don't know what you are referring to re "brushing off" a fitting.

There is no such thing as a guarantee you will kill 100% of the bacteria - but that's the goal.

Your sediment filter is exposed to chlorinated water - correct. Your carbon block, at least the exterior of it, is also exposed to chlorinated water. What about the block interior? I'd replace it.

Russ @ BFS

Keep it in place - you want to sanitize it as well.

Re sanitizing the membrane - it can be done, but remember that the bacteria is within the membrane, so you'll nee to run the sanitizing solution through the membrane under pressure - it typically takes multiple cycles, running water in first one direction than the other, to sanitize a membrane.

This process is typically reserved for larger, more expensive systems.

Russ @ BFS

Thx, all these info are valuable. It just hurt me that I am going to spend money to replace the filter that I just replace and on top of that add a new membrance

In an effort to wrap this thread up with a happy ending, my boss, Charles Mitsis, had a phone conversation with Infinitereef late Friday afternoon. Here are some highlights that might be good info for others.

Sanitizing the housings with bleach does kill the bacteria.

Sanitizing the membrane with hydrogen peroxide (0.3-1.0%) worked quite well for you. As long as you're getting the % rejection performance that you are, the membrane is good.

Bacteria probably didn't make it THROUGH the membrane, so your downstream DI cartridge should be fine.

There will be something "special" in the mail for you, Monday.

If we can help help in any other way, please let me know.

Scott
SpectraPure, Inc.

Dang, sounds like pretty good customer service! Glad it worked out for you.
FB

now thats customer service...BUMP!!!!!!!!!!!!!