For your water I'd have Neocardina shrimp. Caridna shrimp like a KH of about 0 with a GH of 4-6 so some calcium and magnesium I believe. the wonder shells would help raise your GH but not raise your PH so that's fine. To lover your PH for them I'd recommend adding almond leaves and only doing top offs for a bit so long as it doesn't produce ammonia.
Amano Shrimp can live in fresh water, but require brackish water to hatch and survive. The adults need a neutral to acidic environment so 6-7 PH. In terms of hardness they should be more hardy and can acclimate to most waters kept for shrimp.