[♠Winp®oClean♠]

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.

Are you using full mains pressure through the DI vessel?  If so, turn it down & let it flow through steady, maybe into a holding tank. The higher the feed tds the lower the flow through the vessel.

[tom2009]

ive just checked out wcw website. they seem like a lot £ but will save on amount of resin used Id imagine. Will ring them in the morning.

[williamx]

I would not use just a di with tap water reading 345tds some weeks I use over 2000 litres of water,I would be spending almost £100 per week on resin

[tom2009]

not full pressure Winp but have been turning the pressure up to fill the tanks quicker. Will slow it down again. fantastic results from the backpack though. brilliant bit of kit.

[tom2009]

which ro then Pure? 

[williamx]

That I cannot help with, because I am only di, tap water 70tds.

But I have heard that the merlin is quite good.

[♠Winp®oClean♠]

not full pressure Winp but have been turning the pressure up to fill the tanks quicker. Will slow it down again. fantastic results from the backpack though. brilliant bit of kit.

You could use two DI's to get the max out of the resin.

[williamx]

It might be better if you post a topic on the best ro unit to use, you should get a better response

[tom2009]

thanks pure , just what I was thinking.

[krave]

My RO produces at 7-9 ppm, can have it down to 5/6 but was worried about having to much pure fore waste and the membrane. Once my resin is done should I just not bother renewing it?