Difficult water profile - Perth

[DustyRusty]

@DustyRusty check with a local aquarium supplier. Many have RO water for sale at prices that will leave most other places in the dust. It's a good way of checking how much difference an RO system can make to your brewing before shelling out for a filter.

Thanks everyone. Unlikely to buy a filter at this stage. As above, just looking at buying demineralised water for each batch. $6 a refill is a pretty good deal.

 

[mischa6262]

Thanks for your help. Interesting. If I understand it correctly, endotoxins are released by bacteria when exposed to that UV treatment. But considering the RO would have filtered out nearly all of the bacteria anyway, wouldn't the potential endotoxin level be so low its benign? I would of course prefer another filter, but this seems a little different to a UV only treatment system which would result in a much higher level of bacteria in the water affected by the UV. I may have misunderstood this.

OK just to clarify for you:
1: An RO will not filter out bacteria
2: Pre treatment of water for RO purposes is usually treated with 5um poly spun pre filter and a 4-7uM Carbon filter to remove chlorine which if not the chlorine will greatly diminish the life of the RO membranes.
3: Also a water softener will also extend the life of the RO membranes (optional) you can get a water softener cartridge that fits a standard filter housing in either 10" or 20".
4: As i said post RO should ALWAYS be UV treated as it then kills the bacteria and in that process this creates the endotoxins
5: The endotoxins can then ONLY be removed with a sub micron filter of around 0.2 micron
6: If you're just going to pass town water through a UV system then IMO good luck i wouldnt be drinking it or RO water for that matter
just offering my expertise in building of RO plants

 

[DustyRusty]

OK just to clarify for you:
1: An RO will not filter out bacteria

I fully respect you have significant experience here but everything I have read about RO systems claims they filter bacteria. If bacteria are around .2microns in size and a RO membrane is only just larger than .0001microns, how do they not filter bacteria? Some quick googling:

https://epa-water.com/does-a-reverse-osmosis-filter-remove-bacteria-from-tap-water/

http://www.mississippiexplorer.com/germs-removed-by-reverse-osmosis/

https://www.culligan.com/home/solut...at-water-problems-does-reverse-osmosis-remove

I acknowledge that if there is something wrong with the system you might have bacteria but in a properly working system it shouldn’t. That is unless everyone is wrong and you know something they don’t. Happy to be convinced otherwise. Thanks for your help

 

[mischa6262]

OK ill re clarify
My mistake, an RO will remove bacteria.
BUT:
If you are treating the water with carbon that removes chlorine, tastes and odours, this in-turn lets bacteria thrive in the water
Which in normal situations you will then get bacteria in the water.
You use UV to remove the bacteria, this then creates endotoxins which need the sub micron filter at a min 0.2uM
(just trying to assist you not tryin to be a know it all smart ass - as no one knows everything)
Ill leave it here now

 

[DustyRusty]

OK ill re clarify
My mistake, an RO will remove bacteria.
BUT:
If you are treating the water with carbon that removes chlorine, tastes and odours, this in-turn lets bacteria thrive in the water
Which in normal situations you will then get bacteria in the water.
You use UV to remove the bacteria, this then creates endotoxins which need the sub micron filter at a min 0.2uM
(just trying to assist you not tryin to be a know it all smart ass - as no one knows everything)
Ill leave it here now

thanks for all your help