Keep it simple. You don't need to add SO4. Can't comment on the alkalinity because I don't know your grist, but I just use dark syrup and do a pils mash for my BDS, so no alkalinity needed.
Point taken but here is the grain bill.
45# Pilsen 1.6 SRM
5# Cara-pils 2.0 SRM
5# Munich 5.5SRM
2# Aromatic 19 SRM
2# Special B 180 SRM
Acid Malt
D90 & D180
So with this grain bill, in your opinion, do I still need to forget about added alkalinity? I was emulating belgian water profiles from the book Brew Like A Monk.
Also, I use BS3 to calculate my recipes. I went and deleted the SO4 to see how it affected the balance and it changed from malty to extremely malty.
I know I could reduce the amount of CL2 to bring it back to just malty but what is the reason for eliminating the SO4?