Melbourne here 

I leave my tanks be in summer. I tend to change the lighting so its on more during the night than the day but besides that I don't do anything special. The temp of the tap water isn't any lower than the tank. I used to use ice bottles and all but it caused all my fish to get ich (cause they hung around in the cool part near the bottles).millym said:hi, im ex perth (spent nearly 25yrs there on & off) now in london uk.
need to ask all you lot still there how the hell do you keep your tank temps down in summer??? esp in perth when it hits the old 40's??? only wondering cos we didnt get into fishkeeping till we moved here & we struggle in london in summer with an overheating tank & ive always wondered......![]()