Might wanna post this in the shrimp section instead, but it depends is your tank planted, how big, are you dosing ferts? You only need mineral supplements if you are using pure RO water? Not sure what shrimp safe is?
20g platy, , 2 x 10g shrimp, 3 x 20g shrimp, 7.5g shrimp and 1 great dane/mastiff puppy.
I would do 10% water changes once a week, and treat the new water with shrimp safe and a water dechlorinator before adding it. I don't add any mineral supplement to my shrimp tank, but you should check your water hardness to determine if you need to add it. I think shrimp prefer moderate hardness?
As GeToChKn mentioned, you should repost in the 'shrimp and other invertebrates' section for more input from experienced shrimp keepers