I’m not a expert on shrimp, but it seems like it might be spreading like a disease or sickness, have you tried moving the sick/dying shrimp into a different tank and treating them for parasites and other sickness?
Again, I’ve never owned shrimp, so im not sure how all they work, but I have a friend who had one sick bottom feeder almost completely destroy their tank from it gaining a sudden sickness. Oddly enough sometimes your guys just get sick and it’s impossible to tell how.
I’d say to remove the sick/suffering ones into a placeholder tank, using the water from the main tank ofc, try treating them, and probably do a water change on the main tank after removing them, just in case it does turn out to be a sickness/disease related issue.
I feel like you’re almost accelerating their death with that many water changes. They are most likely going into shock from that many.
Did you test parameters after your initial water change after your first reading? Your ammonia was high presumably from the fish using the rest room without a water change but I honestly feel you should stop water changes, retest parameters and then see what you can fix.
Are you giving them any supplement for calcium as well? They could be failed molts but I doubt you wouldn’t see that after 6 months.
Begonethot212 
I’m not a expert on shrimp, but it seems like it might be spreading like a disease or sickness, have you tried moving the sick/dying shrimp into a different tank and treating them for parasites and other sickness?
Again, I’ve never owned shrimp, so im not sure how all they work, but I have a friend who had one sick bottom feeder almost completely destroy their tank from it gaining a sudden sickness. Oddly enough sometimes your guys just get sick and it’s impossible to tell how.
I’d say to remove the sick/suffering ones into a placeholder tank, using the water from the main tank ofc, try treating them, and probably do a water change on the main tank after removing them, just in case it does turn out to be a sickness/disease related issue.
I feel like you’re almost accelerating their death with that many water changes. They are most likely going into shock from that many.
Did you test parameters after your initial water change after your first reading? Your ammonia was high presumably from the fish using the rest room without a water change but I honestly feel you should stop water changes, retest parameters and then see what you can fix.
Are you giving them any supplement for calcium as well? They could be failed molts but I doubt you wouldn’t see that after 6 months.