Alright. Silicone sealer is used to seal the inside of tanks, so yes certain types of silicone are safe. I know there are some silicone sealers that are not recommended for aquarium use, although depending on how much it touches the tank water, it may not even be an issue if what you used is not considered "aquarium safe."
Even the silicone that is not considered "safe" is likely alright if you soak it long enough. Even treated lumber will become fish safe over time if it is exposed to water and the elements for long enough.
Check the label or call the manufacturer/ visit their website if it is not on the label to make sure.