Hi Ozchick,
I use Vetafarm Spark Liquid Concentrate. It's a liquid to add to their water. It helps stablize their electrolites, as animals electrolites become stressed out in extreme heat. I have used this for awhile now and haven't lost any birds from heat.
It contains Glucose, Citrate ions, Bicard ions Sodium ions and Potassium.
I bought mine from a leading pet store in my area, but when I had a look at the lable it is produced in Wagga Wagga.
5ml to 250ml of water, it goes along way.
I also put a half a teaspoon of vitamine C power to 2 litres of drinking water.
Vitamine C helps alot to during breeding times and during molts.