Spectrapure Maxcap 90 - TDS issues

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Dweezilz

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So this is my first rodeo with my used MaxCap 90 (or any RODI for that matter) I purchased used here about 5 months ago. We are purchasing equipment slowly and I've been watching a zillion BRS videos and learning since last August so I'm just now getting to set it all up. I followed AZDesertRat's instructions to clean but did make a few mistakes. Sorry if this is long, but here is what I've done so far:

I threw out all of the filters and the membrane since it was sitting and dry. It didn't have a flush kit so I purchased one and installed it per Spectrapure support's diagram they sent me. I cleaned out all the canisters and membrane housing with a little dawn and water and rinsed fully until 100% clear. I added the canisters and housing back empty and then added 2.5 tablespoons of regular bleach in the first canister. I ran the bleach water through the entire system for an hour and then flushed for an hour to get more flow through the membrane housing. I then drained the canisters and housing of water and ran them again for 30 minutes. I then added the pre-filter and carbon, running the system for 30 minutes . Mistake one was not doing them one by one per AZDesertRat and mistake 2 was I did not rinse the canisters in the sink before adding them. Not sure if either mattered much. I then added the membrane and reattached it all. I kept the flow restrictor that came with it although did cut it down from 2:1 to about 3.5:1. The pre-filter and carbon filter were from saltwateraquariums and were both 0.5 micron generics. The membrane I got was a Dow Filmtec TW30-1812-100HR from Amazon. It is authentic. I read it's the same as the regular Spectrapure 90. It's rejection rate is 98% @ 60psi according to the site. Seems it should have been fine.

My issue is that I get 19-24 TDS after the RO membrane no matter what I do. I've taken everything apart, cleaned the canisters again, rinsed the pre and carbon filters...still the same. So everything else seems like it's correct. I get about 3.5 to 1 waste to product, I have about 58-61PSI on the gauge so pressure is adequate. According to the Cleveland water website, they use Chlorine and there's no mention at all about Chloramine so that doesn't appear to be an issue. My TDS from the faucet ranges from 94 to 110 depending on the moment but it's never been higher and is usually 98. The membrane by the way is 100% seeded perfectly and the gaskets and rubber is all good from what I can see. My water after the filters tests at exactly the same as the faucet which is 105 today. Still, after the RO it's 22 today. I'm using the inline TDS meters, one of which is brand new. I also have a hand held which reads a bit higher (didn't calibrate) but it's consistent with my measurements.

Today I ordered an authentic Spectrapure membrane and all new filters. The previous filters were a huge waste it seems. I never opened my authentic Spectrapure DI's so those are still fine.

If anyone has any ideas about what could be wrong please let me know. I've come to the conclusion that either one of the filters had some sort of contaminant on it that didn't wash off and that ruined the membrane or the membrane was bad out of the box. I suppose it's possible the RO housing is bad and leaks waste water into the product line??? I can't think of anything else unless somehow not all of the bleach washed out and ruined the membrane.

Thanks everyone!!
 

LRT

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Are you running DI resin?
I have 4-500 ppm water out of faucet.
Brand new filters and membrane gets me to about 5ppm from membrane. Thats after a few minute flush before I send it to membrane.
My DI resin is what gets me to 0 tds.
 
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Dweezilz

Dweezilz

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Are you running DI resin?
I have 4-500 ppm water out of faucet.
Brand new filters and membrane gets me to about 5ppm from membrane. Thats after a few minute flush before I send it to membrane.
My DI resin is what gets me to 0 tds.
I have not put them in yet. I need to get to the point where I see 5 after the RO so I don't rip through the DI. Probably not a good idea to run 22 TDS water through the DI. :) Right now I'm at 78% rejection which is obviously really bad thus something is wrong. At 98 TDS from the faucet, even 4 or 5 after the RO would be only average rejection (5 would be 95%).
 

LRT

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I have not put them in yet. I need to get to the point where I see 5 after the RO so I don't rip through the DI. Probably not a good idea to run 22 TDS water through the DI. :) Right now I'm at 78% rejection which is obviously really bad thus something is wrong. At 98 TDS from the faucet, even 4 or 5 after the RO would be only average rejection (5 would be 95%).
It takes me half hour to get to 5 from membrane on brand new filters and membrane even after a flush. I start send my water to DI at around 15-20. My bad for confusion on last post.
 
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Dweezilz

Dweezilz

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No problem at all. I've had it running through the system without the DI's for probably 3 to 4 hours total now and no luck getting the TDS below 20. I sure hope I simply contaminated my membrane somehow and the new one will be fine, but I also don't want to spend money wasting membranes if there is actually some other issue. This hobby is definitely a challenge on every level!! :)
 
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Check to see of your TDS meters are accurate. Pop the post RO TDS electrode into a cup of tap and see if you get 98 TDS. Then we can rule ou5 TDS meter error. Trying to trouble shoot each thing one by one till we hopefully find the issue.
 
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Dweezilz

Dweezilz

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Check to see of your TDS meters are accurate. Pop the post RO TDS electrode into a cup of tap and see if you get 98 TDS. Then we can rule ou5 TDS meter error. Trying to trouble shoot each thing one by one till we hopefully find the issue.
The TDS meters are fine. One is brand new and even the meters at the end of the empty DI canisters both register 22 TDS. As mentioned I also have a hand held meter and I've taken samples in a cup from the hose before and after the membrane and the hand held reads the same as the inline. About 98-100 before and around 20-24 after.
 

Water Dog

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Hmmm. Though I do perform the bleach sterilization process to the unit whenever I change prefilters, I’ve never used soap like Dawn to scrub out the unit. Is it possible that there could be leftover soap residue?
 
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Dweezilz

Dweezilz

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Hmmm. Though I do perform the bleach sterilization process to the unit whenever I change prefilters, I’ve never used soap like Dawn to scrub out the unit. Is it possible that there could be leftover soap residue?
I don't believe so. In AZDesertrat's instructions he mentions cleaning with light dish soap so I'd think that part was fine. I ran water in the sink dumping out the canisters until no suds were left. I'm just starting to think unless somehow waste water is leaking into product in the membrane enclosure, somehow I fouled the membrane or it came that way. I just have zero clue how. Frustrating.
 
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