You’re missing the ammonia test, probably the most important one at this point. Strips cannot be trusted, ditch them, and get the api master test kit and the liquid kh and gh kit.
NO3 and NO2 are dramatically off in color. Hard to get a good reading. I also use test strips but not this brand. Lots of hardcorers HATE strips. I just switched to them for convenience and keep my API master as a good double check. As stated you definitely need to test for ammonia. Ph may be a tad too acidic. Looks like low hardness which can cause sudden spikes like you mentioned. How do the plants look? Sometimes shrimp also just unalive (they only live to 1-2 yrs typically). Id retest w a good kit and see what needs to change from there
To everyone who had such insightful ideas, I thank you! As a response I have ordered an api master kit and it should be here in a day or two once I get the actual readings I’ll update everything! Thanks again to everyone!
2 month old tank + sponge filter means that you probably aren’t fully cycled and are not doing consistent water changes which leads to high ammonia levels. It also could just be shock from new water parameters, as there was only one death.
First time seeing an API strip — both nitrites and nitrates are so off in colour than what’s in the chart so I can’t even interpret that. If you’re raising shrimp you need to resign yourself in investing for a good water testing kit since water parameters are very important.
Another overlooked cause is copper. If you have copper plumbing in your home, copper will be present in your tap water, which is extremely toxic to invertebrates.
No ammonia test, main part in getting a tank cycled and safe for livestock to be in. Plus, test strips cannot be trusted, they aren’t accurate. There’s a decent chance all/any results you got were inaccurate. Pick up an liquid API Mastertest kit and the liquid GH/KH test
Adventurous_Barber_7 
You’re missing the ammonia test, probably the most important one at this point. Strips cannot be trusted, ditch them, and get the api master test kit and the liquid kh and gh kit.
NO3 and NO2 are dramatically off in color. Hard to get a good reading. I also use test strips but not this brand. Lots of hardcorers HATE strips. I just switched to them for convenience and keep my API master as a good double check. As stated you definitely need to test for ammonia. Ph may be a tad too acidic. Looks like low hardness which can cause sudden spikes like you mentioned. How do the plants look? Sometimes shrimp also just unalive (they only live to 1-2 yrs typically). Id retest w a good kit and see what needs to change from there
To everyone who had such insightful ideas, I thank you! As a response I have ordered an api master kit and it should be here in a day or two once I get the actual readings I’ll update everything! Thanks again to everyone!
A high quality test strip is like a high quality condom… 99% of the time…
2 month old tank + sponge filter means that you probably aren’t fully cycled and are not doing consistent water changes which leads to high ammonia levels. It also could just be shock from new water parameters, as there was only one death.
First time seeing an API strip — both nitrites and nitrates are so off in colour than what’s in the chart so I can’t even interpret that. If you’re raising shrimp you need to resign yourself in investing for a good water testing kit since water parameters are very important.
Another overlooked cause is copper. If you have copper plumbing in your home, copper will be present in your tap water, which is extremely toxic to invertebrates.
The first issue you have is using those test trips. Extremely inaccurate. Get the liquid kit and check phosphates as well
No ammonia test, main part in getting a tank cycled and safe for livestock to be in. Plus, test strips cannot be trusted, they aren’t accurate. There’s a decent chance all/any results you got were inaccurate. Pick up an liquid API Mastertest kit and the liquid GH/KH test
Without an Ammonia reading to evaluate, your Nitrite is above 0. Your tank isn’t cycled if nitrite is over 0.
What is your water source? It looks like GH and KH are both 0?