Tunze magnet Strong+ on 1/2" glass

[Nixmo]

Hi everyone. My tank is 12mm (1/2") glass. Is there such a thing as the Tunze magnet strong+ being too strong? Anyone run the stong+ on 12mm without scratching or should I get the strong (no +)?

 

[BanZI29]

As long as you don't drag or move it across the glass. should be OK. maybe a peice of thin felt on the dry side of the glass.