crystal stuff just sounds like aquarium salts... this could be part of the problem if you heavily dosed the tank.
read here about cycling your tank-
http://www.caudata.org/cc/articles/cyclingEDK.shtml
it could take up to and over a month so in the mean time its probably easiest for you to place him in a bucket and change all the water daily. make sure you buy some dechlorinator drops too.
it depends on what colour axolotl as to whether this white fleck could be a problem, golden albinos are normally covered in irridescent spots, this is natural pigmentation. wildtypes also may have some greyish patches. is the fleck fuzzy?
putting them in the fridge slows down their metabolism stopping the spread of any bacteria and also calms them down, they thrive in cooler temperatures.
im guessing the temperature is quite high... in the mid twentys seeing as you are in aussie. you need to purchase a thermometer, this will let you know when you need to start taking action to cool the water.
you will also need to purchase ammonia, nitrite and nitrate test kits to see when your tank is finished cycling. you can start it off by adding established filters from running tanks or by adding substrate from a running, healthy tank. if you dont have access to any of these then you will have to cycle it the other way, putting small bits of axie poop or food in each day will give the bacteria something to eat so they can do their bit.
i know starting with axies is a confusing thing and it seems there is so much info you need to know but dont be intimidated... its pretty easy when you get the basics! i hope i helped and welcome to the forum