# Filtering Water.. which unit to buy ? RO or 3 Stage



## Grainer (24/1/16)

Hi All,

I have decided to get a water filter for my brew rig and a little unsure what to get.. 

2 options are similar to these
3 Stage Purification system: http://www.psifilters.com.au/40-triple-undersink/10324-psi-333-triple-undersink-premium-model.html
Reverse Osmosis: http://www.psifilters.com.au/undersink-reverse-osmosis-systems/10055-4-stage-reverse-osmosis-under-sink-unit-standard-model-021-4s.html

I was wondering if people who are familiar could help out and tell me the major advantages/disadvantages of each system

cheers

Grainer


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## TheWiggman (24/1/16)

I'd go the RO for sure. Does everything the multi stage filter does with the benefit of removing minerals for a cleaner slate for brewing. You can always add what you need later and have better reproducibility between brews as your municipal water changes. The main benefit of the straight filter is the flow rate. RO is notoriously slow especially if you have a low supply pressure.


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## seamad (24/1/16)

I bought one of his RO units for my surgery, ( steam injection autoclaves need really pure water ) about 10 years ago, still going, with membranes replaced of course. I needed a booster pump to increase pressure, but I'm on tank water, you still may need one. If you are just using it for brewing then I wouldn't bother with the tank, it's not big enough for brewing anyway. At work I just fill up some blue willow containers straight from the hose that comes out of the RO filter, just keep an eye out for when they fill up. The unit you linked will make about 8l/hr @50 psi, so it's going to take awhile to get enough for a brew.
Agree with Wigg in that for brewing RO is the best, you can then make whatever water you like


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## dicko (25/1/16)

Slightly OT but I use an RO filter and I fitted a cheap float valve into a 60 litre fermenter and the flow cuts off when the vessel is close to full...
A Pic will say it all


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## mabrungard (1/2/16)

The need for RO is dependent upon your tap water quality. If the tap water has very mineralization, then getting a RO unit is bordering on needless. But if the water is full of mineralization, then RO is perfect. The RO unit includes the 3 stages of the other filter unit you are looking at.

The 3 stage filter unit is less useful since all it can remove is chlorine compounds and taste and odor compounds. The mineralization will not be altered with that filter. 

By the way, those prices are pretty high compared to US equipment...even with the currency conversion. I suppose that there are other factors at play in Oz?


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## Camo6 (1/2/16)

Good advice given here Grainer. I went the RO option without the tank so I had the option to start with a blank slate. Does take a while to fill a vessel though. Luckily the membrane is easy to bypass and I tend to just use the filters and only use the RO filter to fill a fermentor for starsan occasionally.
I bought a cheap TDS meter and the difference between the RO and filtered Melbourne water was about 25 PPM.


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## CmdrRyekr (1/2/16)

The need for RO is somewhat overstated. You can make a clean Pils for example with carbon filtered tap water. It certainly helps to understand your existing water profile and have the ability to adjust it, but it's not the be-all and end-all.

Bunnings retail a 2 stage filter kit for $99 which takes standard 250mm filter cartridges. Spend a few bob extra to replace the kit supplied filters with a 2 micron filter and a 0.2 micron Carbon filter, and while you won't strip the minerals, it does a bloody fantastic job stripping chlorine/chloramine and other odour and flavour causing compounds, instantly leading to improved beer. This solution has finer filtration capabilities than the linked solution, at around 50% the price.

Kit: http://www.bunnings.com.au/stefani-double-stage-undercounter-filter-_p5090104
0.2 micron: http://www.bunnings.com.au/filter-water-stefani-sub-micron-perform-0-2pm-107_p5090025
2 micron: http://www.bunnings.com.au/filter-water-stefani-carbon-2pm-nominal-104_p5090022



mabrungard said:


> I suppose that there are other factors at play in Oz?


Fear and profiteering. Qld introduced fluoride into the water a number of years ago, to some public backlash, and the public were then clamouring for anything that would filter it out of their water. Thus excessively high prices for something that's actually quite cheap, at least in the case of the regular filters (RO a different ball game obviously)


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## TheWiggman (15/2/16)

mabrungard said:


> By the way, those prices are pretty high compared to US equipment...even with the currency conversion. I suppose that there are other factors at play in Oz?


Yes unfortunately a lot of our stuff is shipped all the way from China, which as you're aware is on the other side of the world if you've watched the cartoons.


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