RODI replacement and possible incorrect reading

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#1
I know this question has probably been asked before. I just changed my RO membrane, the two carbon filters, and the sediment filter. The RO membrane I got is rated at around 98 percent. My water pressure is about 90psi according to the meter.

After changing this, my tds is still around 45. After using the same tds inline meter on my main water it reads 420. So the RO is filtering at around 90 percent.

My question is, did I install the filters correctly to get this high reading? Is there a breaking in period? Or maybe my tds meter is broken? (just for background, I bought this unit used and it never read 0 tds from the get go) I have a DI cartridge as well but the color indicator says its still ok to use.

If there is anyone who lives around the Orange area that has an dual inline tds meter and do not mind me borrowing it double check mine it would be appreciated as well.

Input please?
 
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#2
After running the unit for awhile the tds is at 27 now after the RO. Is this acceptable if the initial reading is 420?
 
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#3
If the TDS after RO stage is reading 42, you will use up the DI pretty fast. Mine is about 7 after RO stages. You have 1 sediment and 2 carbon filters and 1 DI canister?
 
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#4
Yeah 1 RO membrane, 1 sediment and 2 carbon filters and 1 DI canister. Right now after the RO it is around 27. I'm just wondering if its just the result of having unclean tap water or if I did something wrong when I replaced the filters.
 
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#5
If your feedwater is 420, and your RO water is 27, that's a 94% rejection rate:
1 - (27/420)=
1 - 0.06=
0.94=
94%

The factory spec rejection rates vary for membranes. Which membrane do you have?

Russ
 
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