I hear of the Python siphon all the time

my pet store always has the video playing on an endless loop so people can watch it over, and over again
As for fishes, I always leave my fishes in the tank when I do a
water change or a gravel wash (siphoning the gravel) and then I just take in water from the Amazon River, I do use a heater but the heater doesn't turn on too often because it is very warm during the day and the heat gets into my house so the only time it does turn on is when I close all of the windows, and doors and then I turn on the
AC, then after a while the heaters will turn on to keep the water the same. Oh and at night too since it will get a little cold.
Other than that, my fishes are all fine outside and inside the house
I hope that helps!
Neji