Losing rocks off back wall

[AquaFlow]

When I was setting up my 55gal tank earlier this year, I painstakingly attached rock to the back wall with black aquarium-safe silicone. In the past few weeks, 2 of the larger pieces at the bottom have come off. Should I try to remove the other large pieces that are still attached or just keep an eye on them? Now I have to figure out how to get the remaining silicone off the glass and how to make the back of the tank less visible to hide my plumbing behind it.
Any ideas/suggestions appreciated.

 

[LiveWire]

If the rocks are going to fall onto corals or possible a fish or have enough weight to possible crack the bottom of the tank then I would just take the remaining ones off of the back of the glass. I would imagine after some time that the silicone bond on the rocks would separate. The glass on the other hand bonds silicone like a magnet so IMO they only way you will get it off is to use a razor blade and some time scraping it off little by little. The razor blade will take it off but be careful if you have some in the corners of the tank that you don't cut into your silicon that is sealing the actual corners.

 

[AquaFlow]

If the rocks are going to fall onto corals or possible a fish or have enough weight to possible crack the bottom of the tank then I would just take the remaining ones off of the back of the glass. I would imagine after some time that the silicone bond on the rocks would separate. The glass on the other hand bonds silicone like a magnet so IMO they only way you will get it off is to use a razor blade and some time scraping it off little by little. The razor blade will take it off but be careful if you have some in the corners of the tank that you don't cut into your silicon that is sealing the actual corners.

So much for listening to my LFS. Was told this would work with no issues as long as the rock pieces were no more than 8lbs each. Hope the smaller pieces don't meet the same fate or I'm going to be in a world of hurt. Luckily, I've just got 1 clown, 1 peppermint shrimp and a small CUC. Also trying to finish removing my crushed coral substrate and replace with sand. When it rains, it pours.