[Mr Sparkle]

Hi guys, my tds keeps going up quite quickly, every time I change resin it's only producing around 2000 litres then tds goes up!

Could it be my ore filters need changing or my carbon block on my ro?

Or is it about right to change resin every 2000 litres?

Many thanks

[James cann]

Nothing to do with your filters it's your resin, sounds like dodgy resin m8.
Get yaself a new bag of tulsion I've got a 25L resin bottle havnt change my resin in over a year and Tds is reading 002, won't change me resin until 015 or 020

[SeanK]

Pre filters have nothing to do with tds, whats the tds of your tap water
and what is the tds after the R.O. ?

[Mr Sparkle]

Thanks for response !
My tap water is high at 220 tds
When put through ro it comes out at around 40 tds
I then put it through di vessel to get it to 0.
It just seems to be rising quick lye just lately!
Was wondering if it might of been something wrong with th ro

[SeanK]

At 220 you should be able to get your water down to 2 or 3ppm my 4040 is going
on six years old and still takes the water down from 220 to 14ppm.
Do you put the water through the R.O. and D.I. in one go
or do you put the R.O. water straight into the tank and put it through the D.I. as needed.
If its the first option be careful your not putting any waste into the D.I. also your water wont be
40 ppm at first, it takes time to come down so you could be getting a lot higher for the first x amount
of litres.

[Spruce]

Your r/o membranes are the issue.  They aren't working efficiently. Sean got there with the answer before I did.

A membrane should have an efficiency of between 97 and 99%.  

Your membrane is working at about 82% so its under performing and as a result you are using much more resin than you should be to reduce the TDS to zero.

At 220 your membrane/s should be purifying your water to a tds of around 4/5. In the old days before the relined our water pipes, we had a tap tds of 254 and my RoMan type 450GPD unit was producing pure at a tds of 4 with a 50psi water pressure.

As chlorine causes premature r/o failure, the carbon block filter needs to be replaced regularily.

How old is the membrane and how often do you replace the prefilters?

[Mr Sparkle]

Yes I  put the water through ro and di  straight away together!

My membrane is about 3 years old and I usually change the ore filters  every 6 months,  last time I changed them was around 4 months ago!

I've never been very good at identifying the problems, so excuse me for keep asking questions lol

Think I will change pre filters and see if that helps!
Thanks guys

[Spruce]

Yes I  put the water through ro and di  straight away together!

My membrane is about 3 years old and I usually change the ore filters  every 6 months,  last time I changed them was around 4 months ago!

I've never been very good at identifying the problems, so excuse me for keep asking questions lol

Think I will change pre filters and see if that helps!
Thanks guys

Sean quite rightly said that replacing your prefilters won't help you lower the tds of 40