Water adjustment questions

This will be my first time adjusting my mash water. I've read the primer, but I have a few questions since I have my actual water report.

First, the data:

pH 7.8
Total Dissolved Solids (TDS) Est, ppm 59
Electrical Conductivity, mmho/cm 0.10
Cations / Anions, me/L 0.7 / 0.7
ppm
Sodium, Na 5
Potassium, K < 1
Calcium, Ca 7
Magnesium, Mg 2
Total Hardness, CaCO3 26
Nitrate, NO3-N < 0.1 (SAFE)
Sulfate, SO4-S < 1
Chloride, Cl 8
Carbonate, CO3 < 1
Bicarbonate, HCO3 28
Total Alkalinity, CaCO3 23
Total Phosphorus, P 0.94
Total Iron, Fe < 0.01
"<" - Not Detected / Below Detection Limit

Grain Bill:

17 lbs 6.9 oz Pale Malt (2 Row) UK (3.0 SRM) Grain 2 88.9 %
13.9 oz Caramel/Crystal Malt - 40L (40.0 SRM) Grain 3 4.4 %
7.0 oz Honey Malt (25.0 SRM) Grain 4 2.2 %
7.0 oz Munich Malt (9.0 SRM) Grain 5 2.2 %
3.5 oz Caramel/Crystal Malt -120L (120.0 SRM) Grain 6 1.1 %
3.5 oz Pale Chocolate (200.0 SRM) Grain 7 1.1 %

Using the EZ water calculator spreadsheet, I'm thinking about adding:

3.5 grams Calcium Chloride
3.0 grams Epsom Salt
1 ml lactic acid (to bring the pH down)

per 5 gallons of water.

These numbers seem to get all the numbers in the recommended ranges and bring the pH down into the right spot.

Looks like my water is very soft and the only thing I'm adding over the Primer's baseline is the epsom salts.

Am I on the right track?

Unless you want to have the bitterness contribution of the magnesium, there is little reason to add epsom salt. In a pale ale, this would be OK. But in less bittered styles, you could easily leave that out. If its the sulfate you're after, then using gypsum may be a better alternative.

I was adding the epsom to raise the magnesium levels for the yeast, since my water is very low in mg. But I don't want additional bitterness, this beer should be malty (strong scotch ale).

So, how does this look:

3.5 grams Calcium Chloride
3.0 grams Gypsum
1 ml lactic acid (to bring the pH down)

I was also trying to adjust the sulfate to chloride ratio for balanced or maltiness. That's why I'm adding something with the CaCl. How important is that?

I use a yeast nutrient at the end of the boil. Will that and the malt take care of the mg levels that the yeast need?

Magnesium is rarely something you need to worry about adding. Plenty (for the yeast) will be freed up in the mash, from the malt.

Personally, I would go for the calculated calcium addition which will bring your mash pH down, skip the salts and the gypsum, and only add the lactic acid if you need to according to your pH meter. If you don't measure your mash pH, I would still err on the side of not using the acid. Spreadsheets can get you close, but acid additions are a delicate thing and I don't recommend them without tools.

I have over-acidified a few mashes, and the flavor is perceptible.

What do you mean by "calculated calcium addition"? Then you say skip the salts, which makes me think you mean don't add the CaCl2.

I have a pH meter on the way. So I should check the pH and only add the acid if needed.

Thanks

As its almost certain that you will need the acid I'd go ahead and add it (consider 2% by wt. sauermalz instead of the liquid - easier to handle and measure and adds some interesting subtleties) and I'd add the calcium chloride too as you are doing that as much for the chloride as the calcium (calcium isn't a very effective means of controlling mash pH - it would take 10.6 grams of calcium chloride in 5 gal to produce the same pH shift as 2% sauermalz). But, that aside, there is no question that a pH check with a decent, properly calibrated meter is better than any spreadheet's calculations or recommendations of mine.