Am I reading this right, that the pH of your tap is mid-6ish and the tank is mid-7, 10x the difference (as that scale is logarithmic)? pH shock would explain/kill.
It also seems minerals might be high, which would explain higher pH as well, have you been topping of evaporation with tap instead of distilled/RO? Such would explain that as evaporation is just pure water leaving the minerals behind, so they’d increase.
In the picture, the left test strip is the tap water after dechlorinating, and the right is the water parameters of my shrimp tank. Last night I decided to test my tank again and topped off with the same tap water. I had two shrimp deaths after checking this morning. I am bamboozled
I’m wondering how big your water changes are and if you use any RO or just tap. Your tap water seems soft while tank seems hard, which is a little strange. Could it be swinging too much with the water changes? Is there something in your tank that could raise the hardness? Some types of shrimp are very sensitive to that kind of thing, and RO soft water is best for them. Do you know what kind you have?
Those tests can sometimes be inaccurate, [these](https://www.chewy.com/api-freshwater-aquarium-master-test/dp/121954) can be more accurate but are also a little expensive. Might be good idea to invest if you’re having water issues. Good luck with your tank and sorry about your shrimp 🙁
Sounds like it could be something effecting the shrimps directly is there any white underbellies? Or odd behaviors?
Any parasites you can see on the heads?(granted you’d probably seen the parasites already)
Going by the stips it looks like there is a sudden swing of pH and hardness.. that might harm the shrimps. Maybe try changing less? Or add the water more slowly?
teriyakiman101 
Am I reading this right, that the pH of your tap is mid-6ish and the tank is mid-7, 10x the difference (as that scale is logarithmic)? pH shock would explain/kill.
It also seems minerals might be high, which would explain higher pH as well, have you been topping of evaporation with tap instead of distilled/RO? Such would explain that as evaporation is just pure water leaving the minerals behind, so they’d increase.
In the picture, the left test strip is the tap water after dechlorinating, and the right is the water parameters of my shrimp tank. Last night I decided to test my tank again and topped off with the same tap water. I had two shrimp deaths after checking this morning. I am bamboozled
3 years? What’s a shrimps lifespan? Maybe they are old and at the edge.
How do you change the water? Maybe you should do the drip method ? Just donit very slowly like when you acclimate them
I’m wondering how big your water changes are and if you use any RO or just tap. Your tap water seems soft while tank seems hard, which is a little strange. Could it be swinging too much with the water changes? Is there something in your tank that could raise the hardness? Some types of shrimp are very sensitive to that kind of thing, and RO soft water is best for them. Do you know what kind you have?
Those tests can sometimes be inaccurate, [these](https://www.chewy.com/api-freshwater-aquarium-master-test/dp/121954) can be more accurate but are also a little expensive. Might be good idea to invest if you’re having water issues. Good luck with your tank and sorry about your shrimp 🙁
Sounds like it could be something effecting the shrimps directly is there any white underbellies? Or odd behaviors?
Any parasites you can see on the heads?(granted you’d probably seen the parasites already)
Going by the stips it looks like there is a sudden swing of pH and hardness.. that might harm the shrimps. Maybe try changing less? Or add the water more slowly?