Did The Heatwave Kill My Cory's?

As was stated in another thread, Southern California experienced record breaking heat levels this weekend. We are currently in the low 90's but reached as high as 120 (no joke) in DTLA. I live in an early 20th century home without central AC. That being said, my 26 gallon planted tank's temperature went up into the high 80's on Friday and Saturday. I did 50% water changes on consecutive days and thought that I made it out of the heat wave with no losses. Well yesterday I came home to 3 dead panda corys, fish that had been with me for over 2 years. The other 2 are missing and presumed lost (they would usually hang out under a cave I made more them in a densely planted tank). All my temperature readings are fine. 0 ppm Ammonia, 0 ppm nitrites, 10ppm Nitrates. I did add 2 tetra fish a few days ago but 1, they are doing fine, 2 they were in a quarantine tank for one week and all my other fish are doing perfectly fine with no sign of stress and no loss of appetite. I bet its safe to assume the warm water lead to their demise. Any other thoughts?

 

I agree it was probably the warmer water. They do best from 72-77. The high 80's probably stressed them too much. Also, being a bottom dweller, warmer water holds less oxygen and that may have contributed.

 

It very well could have been the warn water that caused their death. Panda cories are one of the more sensitive species of cories.

 

That's unfortunate that the heat wave killed your cories. It's such a freak thing sometimes...I guess next time you could put some frozen bottle waters in the tank to help cool it and unplug the heat just in case.

 

Panda are cooler temp fish. They like around 72, so if it went up to 88 or high of course they are gonna die. They are getting ready to be eaten . That is also very low oxygen, so I hope your filters are working. An increased temp in the water causes stress, so yeah they could die. Try to put a fan above the water.