Enyo micro star cloths.....around $50 if i remember correctly.
Stray water on the glass and wipe of......works wonders.
I was showen a test where the lady wiped butter on the glass of my cage...

.
To my amaznment she sprayed cold water on it; then wiped it off....no streaking!!!
Best part is you dont have to use chemical cleaners etc.
I have however throwen a few away with cage waste paper :roll: