[martinj]

Help Ive had my ro system for about a year and havent flushed it regularly, the prefilters had been in for about 9 months before I changed them and the tds before water goes into di is 40 after resin its 20 but production time and waste havent gone up? What the hell is going on have I knackered the membrane? any help much appreciated thanks

[chez]

you have probably answered your own question mate.
You really do need to flush the RO regularly to keep it healthy, otherwise its going to eat up your resin too quickly. Its about management of your system weekly so as to keep it producing pure water. I don't know wether you can save it now by giving it a good flush or it might be a new one but look after it!! Prefilters should be changed 3 monthly really.
The Water coming out of the RO should be about 14 based on maybe 320 ish hard water to start with.
Hope it helps