Magnesium level, other questions

Below is my city water profile. I know what I need to changr for everything but magnesium. Some places say about 20 ppm is about the highest you want to avoid spur flavor and a diuritic effect, some say up to 100 ppm os fine. Is 60 too high and if so is there an easier way to reduce leves than using slaked lime? That procedure requires treating all the water in another vessel and Id often have to treat 15-20 gallons at once.

Calcium (Ca ppm) = 30
Magnesium (Mg ppm) = 60
Sodium (Na ppm) = 4.2
Chloride (Cl ppm) = 7
Sulfate (SO4 ppm) = 9.3
Bicarbonate (HCO3 ppm)
Alkalinity (CaCO3 ppm) = 70

Thanks

You have already brewed with this water, I presume. Do you taste off flavors with the water as it stands now?

I actually had attenuation trouble when i switched to all grain last December and I assumed it was because the city softened the water or had something else to do with my water so my buddy i brew with would bring his tap water over and we had no problems. I havr since determined we probably werent maintaining mash temps at that time but have not tried my water again yet. Now that we mostly brew 10 gallon batches its becoming more of a pain to get his water over so we want to figure out how to make adjustments to my water.

There are errors in the concentrations reported above. The cations and anions don't balance nearly well enough. For the reported alkalinity, the bicarbonate content would be around 85 ppm. The Mg content of 60 ppm is a little suspect since it frequently exists at concentrations that are lower than the Ca content. 60 ppm Mg is on up there, but it shouldn't be at the diuretic level. Are you sure that it was 60 ppm and not 60 ppb? If the profile was with 60 ppb Mg, then it comes much closer to balancing the cations and anions.

I copied the numbers from the email the water dept supv sent me. Maybe I should have ward labs test it. I might be worrying about something that is in fact nothing to worry about.