When to add gypsum & how much for partial boil?

[danno_lee]

I am doing my first partial mash today, and I was wondering if I could implore you fine folks for a bit of advice on the use of gypsum. I am brewing a 5 gallon Paulaner Hefe-Weizen clone. My largest pot is 5 gallons, so I am doing a 3.5 gallon partial boil. In order to get my mineral levels where I want them (59mg/l Ca++ and 122mg/l SO4-) I am to use 3 grams of gypsum for the 5 gallons of water.
Do I add all 3 grams to my 1 gallon of mash water, or should I add 0.6g to the mash water, 0.6g to the sparge water, 0.9g to the 1.5 gallons that I am adding for the boil, and 0.9g to the top off water?

 

[Lagger]

I added mine to the mash, sparge & boil as 3 separate additions. If you add all to mash might lower ph too much

 

[danno_lee]

I added mine to the mash, sparge & boil as 3 separate additions. If you add all to mash might lower ph too much

That's what I did for my last brew, as I figured it was the safest way to go about it, but I haven't seen any other opinions regarding whether to add it in stages or all at once. Thanks for the reply!