I would examine the dead fish and look for damage (Bird or cat attack marks like missing scales etc) and signs of disease (Cotton wool like strands, white spots etc) I'd also do a complete water test and remember to check for deadly poisonous things like Ammonia and Nitrite. If that is not the problem, I would empty the pond completely and clean/disinfect the whole thing and start all over again.
it's dead
Some can be found in pond water but not all.
Surface of water
It is a bug that can be found in small shallow puddles or in a pond It is a bug that can be found in small shallow puddles or in a pond It is a bug that can be found in small shallow puddles or in a pond It is a bug that can be found in small shallow puddles or in a pond
Algea, protozoans, and other microorganisms can be found in most pond water.
The number of fish typically found in a pond can vary depending on the size and conditions of the pond, but a small pond may have around 100 to 200 fish, while a larger pond could have several thousand fish.
in a pond
If its an amphibious turtle, I don't see why it would. a turtle on its back may have trouble on dry ground, but in the water, its no issue, unless it because lodged underneath something.
they are usually found in freshwater or pond water
rocks
your mom is in there
H2O