[Steve CM]

i have just noticed my water is at 005ppm

It is coming out of my RO at 007ppm so my resin is shot.

I changed my resin about 4 months ago i have a twin DI and now one sits at 6ppm and the final one at 5ppm

i can't work out why my resin has shot that quickly at such a low ppm from the RO

does anyone know how to calculate the wmount of litres i ahould get from 1 full bag of resin with the ro sitting at 7ppm?

anyways we are working with 5ppm water at the moment until i can work out whether the usage is correct. i have tested the water on my own windows and its fine. no complaints either so i'm sure the water is fine

I'm just scratching my head a little here

[gary999]

i have been working with water 4-5ppm for weeks now
no probs at all,slightly easier to work with zero though

[formb]

Be careful if you are using anything over 000. The resin catches particles in the water, once the resin becomes saturated the tds goes up. It can go from 001 to 100 quite quickly depending on the size of your demin vessels.

We never use any thing but 000. We change our resin every 5 - 6 months and our RO is 003. To ensure we dont throw away good resin we have two bottles in series as soon as we get 001 at the hose we move the second demin bottle back to nearest the tank and replace the resin in the other, putting it back nearest the hose

[chopsie]

I have read on here someone using water up to 20ppm with no trouble,one bloke at least uses rain water without doing anything to it at around 16ppm I believe,I think just change resin as soon as from what i have gathered,I am only learning myself,but lads on here seem to say change it once it gets to about 5ppm

[williamx]

I go upto 10ppm with no problems whatsoever.

To calulate you resin the formule is 500000 divide by the tds = litre of pure water from 25 litres of resin using a single di tank.

[karygate]

there is a few people by me it comes out from ro at 5 to 10 so they never use resin. my pressure is not good enough or i would do the same.

[Ian Lancaster]

We use up to 009.  If my RO would produce at up to 007 I wouldn't bother with resin. 

The measurement '000' is arbitrary.  It means less than one part per million, but that is just a convenient measurement.  For electronic parts washing they measure in parts per billion,  There's no fixed rule that says you must have less than one part per million, it's a case of try it and see.  If it works at 7, or 10 or even 20 parts per million, that's fair enough.

[tacky]

i thought so

[♠Winp®oClean♠]

We use up to 009.  If my RO would produce at up to 007 I wouldn't bother with resin. 

The measurement '000' is arbitrary.  It means less than one part per million, but that is just a convenient measurement.  For electronic parts washing they measure in parts per billion,  There's no fixed rule that says you must have less than one part per million, it's a case of try it and see.  If it works at 7, or 10 or even 20 parts per million, that's fair enough.

Agreed.

Personally I wouldn't bother with 2 DI's if it comes out of ro at 007.

I use a second DI but my tap water is 90ppm so I can exhaust the resin up to that 90ppm. (di only)

[gary999]

this is when this forum really works when i first started if
ppm went above 0 i would ordering resin.trial and error
and use over time plus good info off here can really save you money
in the long term.

suppliers must really hate it

[matt]

Be careful if you are using anything over 000. The resin catches particles in the water, once the resin becomes saturated the tds goes up. It can go from 001 to 100 quite quickly depending on the size of your demin vessels.

It is coming out of my RO at 007ppm so my resin is shot.

this is the key on the post, it comes out of the RO at 007, so its not going to shoot up ( and certainly not to 100 )

at 007 i wouldnt bother with DI, my DI has now work out and the RO is producing 009 at the mo, which says to me my RO has about 6 months left, then its time to replace it

[matt]

this is when this forum really works when i first started if
ppm went above 0 i would ordering resin.trial and error
and use over time plus good info off here can really save you money
in the long term.

suppliers must really hate it

the difference between 000 and 007 is nothing in our terms

so why bother with DI if your RO is producing at 007

[Steve CM]

i have 2 bags of dowex just sitting there to. i think there may be something wrong with my tds meters or one of them. i took two readings earlier. one said 7ppm after di the other 5ppm.

I'll think i'll chuck the first one as its not being to kind to me

[paulben]

I go up to 8ppm no prob reckon could go higher

[ps outthere]

A few months ago my tds went from 3 to 22 within a few days. I had been using the 22 for a full day, didn't get one complaint. I still try to use it below 5, for my own peace of mind.

[roundbuilder]

i was told by a customer who works with purities with ppb that anything under 30ppm is naked to the human eye, however soon as mine gets to 10 i still change

[tom2009]

I go upto 10ppm with no problems whatsoever.

To calulate you resin the formule is 500000 divide by the tds = litre of pure water from 25 litres of resin using a single di tank.

so if I've got a tds of 325 I should get 1538 litres of water from 25 litres of resin? after going through the pressure vessel the water is still only 005ppm at best, won't seem to go any lower. am I doing something wrong? made another 75litres tonight (only use a backpack) and noticed the tds is going up, now 009ppm.

[williamx]

I go upto 10ppm with no problems whatsoever.

To calulate you resin the formule is 500000 divide by the tds = litre of pure water from 25 litres of resin using a single di tank.

so if I've got a tds of 325 I should get 1538 litres of water from 25 litres of resin? after going through the pressure vessel the water is still only 005ppm at best, won't seem to go any lower. am I doing something wrong? made another 75litres tonight (only use a backpack) and noticed the tds is going up, now 009ppm.

Tom

If you have tds of 325 you really should put this though a ro unit, this should bring it down to 20 or below, you then finsh it off by rinsing though a di tank

[tom2009]

I go upto 10ppm with no problems whatsoever.

To calulate you resin the formule is 500000 divide by the tds = litre of pure water from 25 litres of resin using a single di tank.

so if I've got a tds of 325 I should get 1538 litres of water from 25 litres of resin? after going through the pressure vessel the water is still only 005ppm at best, won't seem to go any lower. am I doing something wrong? made another 75litres tonight (only use a backpack) and noticed the tds is going up, now 009ppm.

Tom

If you have tds of 325 you really should put this though a ro unit, this should bring it down to 20 or below, you then finsh it off by rinsing though a di tank

how does that work Pure?  I've been meaning to ask this for ages. thanks for responding               

[williamx]

I go upto 10ppm with no problems whatsoever.

To calulate you resin the formule is 500000 divide by the tds = litre of pure water from 25 litres of resin using a single di tank.

so if I've got a tds of 325 I should get 1538 litres of water from 25 litres of resin? after going through the pressure vessel the water is still only 005ppm at best, won't seem to go any lower. am I doing something wrong? made another 75litres tonight (only use a backpack) and noticed the tds is going up, now 009ppm.

With a ro unit the water goes though various stages of filtering, this takes time and there is waste water as a by product.

A di unit filters the water in one stage with no waste.

It like charging a battery you have a trickle charge (ro) or fast charge (di)

Tom

If you have tds of 325 you really should put this though a ro unit, this should bring it down to 20 or below, you then finsh it off by rinsing though a di tank

how does that work Pure?  I've been meaning to ask this for ages. thanks for responding