Random fish dying and not sure if i have an aggressive fish

[Naughts]

To be honest i dont know my GH, haven been able to get a api test dor that

Does your water companies website show the GH in a water quality report?

 

[Jose Sanchez]

Does your water company website show the GH in a water quality report?

no, i tried but it seems that is not information shared in Mexico, i had been trying to get one of those GH/ KH API test kits for a while

 

[threecharacters]

The baby cory was born in the tank in March, is a paleatus or peppered, the tank is at 77,78 F constantly
The neons are just a couple of months since I bought them
Thanks!

Isn't that too hot for Peppered Cories? Peppered Cories are more of a coldwater fish, able to handle temps down into the 40s. I remember reading an account where wild Peppered cories were found in icy streams (here -> https://www.practicalfishkeeping.co.uk/features/focus-on-commonly-kept-corydoras/ and here -> https://www.fishforums.net/threads/extremely-cold-water-peppered-cory-cats.449693/).

Still, not sure why the neons or cherry shrimp died. Perhaps the neons were not of quality stock? Years of commercial breeding has harmed the genetic strength of neons. How long have you had the neons?

 

[HoldenOn]

Isn't that too hot for Peppered Cories? Peppered Cories are more of a coldwater fish, able to handle temps down into the 40s. I remember reading an account where wild Peppered cories were found in icy streams (here -> https://www.practicalfishkeeping.co.uk/features/focus-on-commonly-kept-corydoras/ and here -> https://www.fishforums.net/threads/extremely-cold-water-peppered-cory-cats.449693/).

Still, not sure why the neons or cherry shrimp died. Perhaps the neons were not of quality stock? Years of commercial breeding has harmed the genetic strength of neons. How long have you had the neons?

Yea peppered cories are cold water, but I'm pretty sure it depends on where they have been raised as well. I keep my tank at 76 and they are fine. Take that with a grain of salt, I'm just assuming.