Reverse Osmosis Water

[Mrobson]

I recently bought a four stage water filter system but I’m yet to brew using the water. I’m just curious if anyone on hear uses one and if so what’s your opinions on the end results?

 

[chthon]

Have you also bought a TDS meter?

I have also bought a RO system a few months ago. I have already used it once. My TDS meter gave me a read-out of 7 ppm, which is almost devoid of minerals. I then added gypsum and calciumchloride to mineralise my liquor. Since I already brewed with demineralised water from the shop, I didn't notice any differences.

Busy today gathering water for Friday. Need to plan ahead a little bit. I use the smallest system available, which gives me 1 l of water per 10 minutes, so I need about two hours, or even a little bit more to gather the amount of water I need (I don't do big brews). I can also get rid of the waste water to my rainwater cistern.

 

[strange-steve]

I'm using mine right now in fact:

I wouldn't recommend using 100% RO water though unless you're adding salts to it (and actually probably not even then).

 

[Mrobson]

I already treat my water from the tap so I’m already used to adding salts. How come you don’t recommend using 100% RO? Is that just personal preference?

 

[Mrobson]

Have you also bought a TDS meter?

I have also bought a RO system a few months ago. I have already used it once. My TDS meter gave me a read-out of 7 ppm, which is almost devoid of minerals. I then added gypsum and calciumchloride to mineralise my liquor. Since I already brewed with demineralised water from the shop, I didn't notice any differences.

Busy today gathering water for Friday. Need to plan ahead a little bit. I use the smallest system available, which gives me 1 l of water per 10 minutes, so I need about two hours, or even a little bit more to gather the amount of water I need (I don't do big brews). I can also get rid of the waste water to my rainwater cistern.

I’ve not bought one yet but it’s on the list. Do you aim for a specific water profile when adding your salts?

 

[Ben034]

Do these need to be plumbed in or can they be fixed temporarily some how?

 

[LeeH]

Have you nailed all other aspects of your procedure before building your water profile n scratch? It’s a very American and arguably unnecessary approach.

 

[kelper]

Many American cities have polluted tapwater, so I can see the attraction of RO. All tapwater in UK is safe to drink.

 

[Mrobson]

Have you nailed all other aspects of your procedure before building your water profile n scratch? It’s a very American and arguably unnecessary approach.

I test my water for calcium & the alkalinity before every brew, the figures then get tapped into the forum calculator, along with what Yorkshire Water say there is.

Yes, I’m happy with how they taste but I’d like to see if they can taste better. The water profile was my next thing to try and tweak?

 

[An Ankoù]

When I lived in Poole, I collected rainwater to brew pilsners. Very little salts addition to get it up to Pilsn profile. Water softeners were around in the day, but the product wasn't promising. I suppose RO technology has moved on a pace.

 

[strange-steve]

I already treat my water from the tap so I’m already used to adding salts. How come you don’t recommend using 100% RO? Is that just personal preference?

There are various trace minerals in tap water that are beneficial to yeast health, so I tend to go 90% RO maximum, and more usually 50%.

Do these need to be plumbed in or can they be fixed temporarily some how?

They can be attached temporarily, mine in the pic above is attached to the outside tap through the window as and when I need it.

 

[Mrobson]

So if I was to use 90% RO I would just input 10% of my tap waters minerals into a calculator to give me the right amounts of salts to add and then tweak it from there?

 

[kelper]

Well, that assumes RO water is absolutely pure. Does your RO system specify how much it can remove from tapwater?

There's a six-stage unit on Amazon and the sixth stage has a "Re-mineralising filter to enrich the water ions with health essential minerals including: Calcium, Magnesium, Potassium and Sodium."

It boasts that is removes "up to 98%" of minerals. That could mean anything!

 

[strange-steve]

So if I was to use 90% RO I would just input 10% of my tap waters minerals into a calculator to give me the right amounts of salts to add and then tweak it from there?

Yep

Well, that assumes RO water is absolutely pure. Does your RO system specify how much it can remove from tapwater?

You're of course technically correct, however it'll only be off by a few ppm which in practice isn't worth worrying about.

 

[kelper]

Has anyone had their RO water analysed? It would be great to see before and after ppm's. I've been working with commercial RO plants since the 80's but these were for making potable water from sea-water. They reduced the chlorides (salt) from about 35,000 to 200, but needed very high pressures. Still, that's a reduction of 99.5%.

I did some research on domestic RO units; a four or five stage unit will remove about 95% of contaminants so you could make a good estimate of what's in your RO water if you know whats in your tap water. Heres a typical datasheet.

Approximate percentage of containments removed by RO.

Aluminium 96 - 98

Lead 95 - 98

Ammonium 80 - 90

Magnesium 93 - 98

Bacteria 99+

Manganese 96 - 98

Boron 50 - 70

Mercury 94 - 98

Bromide 90 - 95

Nickel 96 - 98

Cadmium 93 - 97

Nitrate 97 - 99

Calcium 93 - 98

Phosphate 95 - 98

Chlorine 98+

Potassium 92 - 96

Chloride 92 - 95

Silica 80 - 90

Chromate 85 - 95

Silicate 92 - 95

Copper 96 - 98

Silver 93 - 96

Cyanide 85 - 95

Sodium 92 - 98

Fluoride 95 - 98

Sulphate 96 - 98

Hardness 93 - 97

Thiosulphate 96 - 98

Iron 96 - 98

Zinc 96 - 98

 

[strange-steve]

Has anyone had their RO water analysed? It would be great to see before and after ppm's. I've been working with commercial RO plants since the 80's but these were for making potable water from sea-water. They reduced the chlorides (salt) from about 35,000 to 200, but needed very high pressures. Still, that's a reduction of 99.5%.

I just checked mine with a cheap TDS meter, tap water is 180 ppm, RO 7 ppm and treated mash water 350 ppm.

 

[kelper]

So that's a 96% reduction. Is your RO a unit costing around £100 or something more fancy?

 

[strange-steve]

£41 on ebay, I think the fact my tap water is already quite soft helps :thumba:

 

[kelper]

I'd just suggest that people use RO water as soon as possible or guard against bacteria as it will contain no chlorine. Also, the filters are prone to harbouring bacteria. Perhaps not a problem if used weekly, but could be an issue if stored damp for weeks on end. Any thoughts Steve?

 

[kelper]

£41 on ebay, I think the fact my tap water is already quite soft helps :thumba:

That's brilliant at that price! How fast does it produce water? Is it just connected to the mains or have you added a pump?