DUDE!!!!! there are dumb questions and then there are DUMB questions... and yours really is DUMB!!!!!!!
j/king
it is a great question, in that i have not heard it before and it really does make you think about if you stop and think about it.. .my suggestion is to not think about it....
hehehehehehe
actually just the opposite... when claening the glass be cautious when near the silicone... dont dig into it... most tanks, (cheaper) tanks have a ton of silicone in the joints so i doubt you will cause any problems and if you do end up peeling a little bit of silicone off, it wont be a problm in trimmin off the loose peace...
more expensive tanks have a small bead of silicone and you would not want to gouge that silicone at all...
there is a cleaning product called Mr Clean MAGIC EREASER that is perfect for cleaning the glass or acrylic... it has no cleaning solution or chemicals but is just a micro abrasive pad... (sponge)
it is perfect for getting into corners and rounded glass...
(except you get your hands wet)