need help with salt and acid additions to RO water

[aussie brewer]

Hi, im planning to brew my first all grain APA from the recipe section of this awesome forum
I am using RO water and im thinking of adding 3g gypsum and 2g calcium chloride to match the water profile below. Do I add the salts to the mash and sparge water or just the mash?

After entering the data into beersmith it calculates a mash pH of 5.54, do I need to add lactic or phosphoric acid to the mash and sparge water? or will the salts bring the pH down to the correct range?
Grain Bill
5 lb 13 oz US 2-Row (2.0 L)
2 lb 11 oz UK Maris Otter (4.0 L)
2 lb German Munich (7.0 L)
6 oz Caramel 20 (20 L)
6 oz Caramel 85 (85 L)


Water
Calcium 75 ppm
Magnesium 0 ppm
Sodium 18 ppm
Sulfate 111 ppm
Chloride 51 ppm

Thanks in advance to the help I really appreciate it!!!
Cheers from Australia

 

[McKnuckle]

The salts do lower the pH, but BeerSmith is already estimating that for you (assuming you've entered them). You can use lactic, phosphoric, or acidulated malt to lower pH further into the 5.3-5.4 range.

 

[aussie brewer]

Thanks Mcknuckle! do I just add them to the mash and not the sparge?

 

[Conehead]

I add salts to the mash and sparge.

 

[Gnomebrewer]

Add salts to the entire brewing water (mash and sparge water).
You might need some acid to lower the pH, but IME BeerSmith pH estimates are a fair way off the mark.
What are you using for 'US 2-row'? (not easy to find and expensive in Aus).

 

[aussie brewer]

Cheers Gnomebrewer! I just had a look at the local homebrew stores catalogue, and they have joe whites pale malt 4.5ebc
What acid would you recommend?

 

[Gnomebrewer]

I've read that they make a 'pale malt', but never seen it for sale. Normally you can only get JW Export pils or JW Traditional Ale. JW Pale malt is 3.0-4.0EBC though.

88% Lactic and 85% Phosphoric both work well for acid.

 

[aussie brewer]

Im going with adding the salts to mash and sparge water, which acid do you guys prefer to bring the pH down? do I acidify the mash and sparge water for this brew?
Thanks a lot for the replies

 

[Gnomebrewer]

Again, phosphoric and lactic are both great. Most US brewers use 10% phosphoric or 88% lactic, because it seems to be difficult to get 85% phosphoric over there. 85% Phosphoric is much easier to get in Australia (it's in all the Homebrew stores I've been in to) and is probably the best option.

When brewing with RO water, you only need acid in the mash - no need to acidify the sparge water (acidify sparge water if it's got high alkalinity).

Is this a 19L (5 gal) batch? If so, I think you'll need a bit more gypsum to hit the sulphate numbers you put in the OP.

Use about 1.5mL of Phosphoric acid in the mash to hit about a 5.4 pH, but even if you don't use any acid your pH is not too high.

Where do you live? Most Australian towns/cities have fairly soft water that is good for brewing, so no need for RO. WA and SA and anywhere inland is a different story though.

 

[aussie brewer]

Thanks Gnomebrewer you are a legend!! I live in Sydney, I have a RO filter already setup for the drinking water

 

[Gnomebrewer]

Ahh, I see, if you have a filter set up then it's worth using. I've never even seen RO water for sale - the only place I've seen it on Oz is Coober Pedy - the whole town supply is RO!

 

[aussie brewer]

I think im good to go!! thanks again for the awesome advice