I would wait until the smell is gone completely before planting. For no other reason other than you'll know the silicone is 100%.
Sounds like you did everything right on the salmon tank. I would do a couple water changes of about 75% before i added new eggs. Say 75% every couple days for a week. Then go for it. But then again, i know nothing about rearing salmon.....lol
Good luck and keep me posted. Btw, got a pic of the salmon tank?