First sour with Roeselare. Mash pH?

[qmax]

So from what I read, I need to adjust a sour beer mash pH like a normal beer.
Long story short, I ended up adding 28 ml of 40% lactic acid for mash and sparge acidification, that gets me 610 ppm lactate anion in the fermentor.
Now I'm wondering if there will be enough lactic acid produced as it is from the bugs, should have I rather gone for phosphoric to treat my water?

My alkalinity is 190 ppm as HCO3-, 55 Ca, 14 Mg.
This is my recipe, a variation on Flanders red (these were the only malts I had)
OG 1.061
10 IBU
4.4 lb German - Vienna 37 4 38.4%
5.05 lb German - Pilsner 38 1.6 44.1%
1.1 lb German - Munich Light 37 6 9.6%
0.45 lb Belgian - Special B 34 115 3.9%
0.45 lb American - Wheat 38 1.8 3.9%
11.45 lb Total

 

[kingwood-kid]

The mash pH should be around 5.2. A finished sour beer will often have a pH around 3.3, which is roughly 100X as acidic as the mash, with almost all of that acidity coming from lactic. You'll be fine.