TDS of rodi

[JKDMan]

I just replaced the filter cartridges in my rodi and maybe 100 gal have passes thru them, I'm getting a tds reading of 55. Could it be the container I hold it in has something contributing or is something wrong with the rodi filter.. i collect the water in a lexan container for restaurants, which is open to the air.

 

[Sticker shock]

Did you really pack down the resin? You want to make sure the water can't find a channel to pass through and essentially miss filtering through the resin.

You could also collect a small sample in another container and measure TDS there to rule the container out as a cause.

 

[JGT]

I just replaced the filter cartridges in my rodi and maybe 100 gal have passes thru them, I'm getting a tds reading of 55. Could it be the container I hold it in has something contributing or is something wrong with the rodi filter.. i collect the water in a lexan container for restaurants, which is open to the air.

Have you flushed your membrane? Could be TDS creep.

 

[JKDMan]

Its a new cartridge I bought pre filled.. it came vacuum sealed

 

[JKDMan]

Have you flushed your membrane? Could be TDS creep.

Its a new membrane, it's been flushed

 

[JGT]

Its a new cartridge I bought pre filled.. it came vacuum sealed

So you replaced the RO membrane as well?

 

[JKDMan]

So you replaced the RO membrane as well?

I replaced everything, poly block, carbon block, ro membrane and di resin cartridge

 

[robbyg]

What is your TDS after the Ro membrane?
Also how old is the Di resin cartridge that you are using and was it stored in an air tight bag?

 

[JGT]

I replaced everything, poly block, carbon block, ro membrane and di resin cartridge

And your TDS in the past has been 0?

 

[JKDMan]

What is your TDS after the Ro membrane?
Also how old is the Di resin cartridge that you are using and was it stored in an air tight bag?

It's all brand new, only passed about 100 gal thru it haven't checked it before di resin, it came from vendor vacuum sealed

 

[newfly]

Depending on the quality of the membrane. My tap water tds is about 200ppm and after RO its <10. The manufacture claimed >90% reduction in tds, which is the case for me. I don't have DI. I assume DI can further reduce the TDS, but i assume there must be a limitation due to flow rate versus absorption rate of the DI.

What is your tap water tds?

 

[JKDMan]

And your TDS in the past has been 0?

Idk, just got a meter

 

[JKDMan]

Depending on the quality of the membrane. My tap water tds is about 200ppm and after RO its <10. The manufacture claimed >90% reduction in tds, which is the case for me. I don't have DI. I assume DI can further reduce the TDS, but i assume there must be a limitation due to flow rate versus absorption rate of the DI.

What is your tap water tds?

I'll have to check

 

[JGT]

Idk, just got a meter

Ah, then the obvious answer could be you have really crappy water.
You may need to add additional DI canister to get down to 0.

 

[JKDMan]

Ah, then the obvious answer could be you have really crappy water.
You may need to add additional DI canister to get down to 0.

I'll have to check

 

[newfly]

Ah, then the obvious answer could be you have really crappy water.
You may need to add additional DI canister to get down to 0.

If post RO is so high, adding a second RO membrane may be another solution. Using DI to reduce 50+tds is going to exhaust the DI resin quickly.

 

[Garf]

Idk, just got a meter

You’re gonna need a TDS meter actually in situ on your RODI unit. I assume you’ve just got a TDS pen or something.

 

[sp1187]

your DI cannisters are in backwards. there's an arrow on the cannister for this way up.

 

[JKDMan]

You’re gonna need a TDS meter actually in situ on your RODI unit. I assume you’ve just got a TDS pen or something.

Yes a pen

 

[JKDMan]

your DI cannisters are in backwards. there's an arrow on the cannister for this way up.

It's in the right way.. up arrow is up