So I sent two water samples to Ward labs and received them Tuesday. The first source is from the well and the second is after my softener. I've made five batches using the well water and they were good. Then switched to using water from after the water softener and the last batches were lackluster. The results from the labs as you might have guessed were way different from each other. I will be using the well water from now on but I have some questions.
If you take the equivalent amounts of magnesium (mg/L divided by 12.15) and calcium (mg/L divided by 20), add them up, multiply by 23 and add the sum to the sodium in the well water you should have something very close to the sodium in the softener water report. At the same time the calcium and magnesium levels in the softened report should have dropped to a very small number. Otherwise the reports should be the same.
1. If I filtered the well water how much could it change the water profile?
Not at all in terms of the things we measure as brewers. Filters are for removing musty, earthy odors, particles of sand etc
2. Both reports listed <.01 iron but, I know there has to be iron in the well source so will it affect the brewing equipment? And if so how would I be able to combat the Iron?
Why does there have to be iron in the well? There is some, of course, but at less than 10 ug/L you don't have to worry about iron's effect on you beer or your gear. As you don't have enough to require combating it I won't go into that.
3. Lastly, using bru n water to get the profiles needed I'm adding about 1.0-2ml/g of lactic acid, liquid 88%. Is there a point at which there could be too much acid?
Yes, the point where you begin to taste it in your beer and find it objectionable. To give you an idea as to where this might be consider that most German beers are going to have about 3% Sauermalz or the equivalent in Sauergut in their formulations because that amount supplies sufficient acid to take care of the malt proton deficits in a typical German beers grain bill. Assuming dough in at 1.5 qts/lb that is equivalent to about 1 mL 88% acid per gallon mash water. We can take from this that 1 mL/gal is not objectionable. OTOH Weyermann has on its website a recipe for Berliner Weiße that calls for 8% Sauermalz. As the main characteristic of Berliner Weiße is its acidity we may conclude that 2 mL/gal, corresponding to 6% Sauermalz which isn't quite 8% but getting close to it might be objectionable. I was just talking to a guy yesterday and the subject came up. He was of the opinion that 6% would be objectionable. Some sort of a test to determine your personal limit is probably in order.
Bru'n water and its author are somewhat cavalier about adding acid to water to deal with alkalinity which should really be dealt with in other ways. Another place to watch out in Bru'n water is its candidate water profiles. It turns out that while many people probably wouldn't figure out how to do it it is possible to match those profiles exactly but to do so requires the use of a fair amount of acid in addition to that required for the malt and alkalinity proton deficits. Turn on your amber warning light whenever the program calls for more than about 1 mL/gal.