Fish Deaths From El Niño?

Hello everyone I had a lot of problem adding fish lately. My last 3 to 4 fish have all died within one day of having them in the tank. I believe I am acclimating them just fine and they all have died within a day. I had someone tell me this was happening to them too and they said it was because of the El Niño. I guess the fish are coming from the waters with there El Nino is and it is somehow affecting them. I'm not sure. Does this sound correct? Please explain if you know! I live on the west coast of the US.