Not much but enough. It started getting coralline in the seam I think. It never leaked. I just figured I had better contact RS. They offered a new one so I took it. I think the actual seal was intact. It just got in the guard.@Jeffcb man I’m afraid of leaks. After the crash in 2017 with my RSR 250 it was awhile before I could drain and clean the tank. It had so much build up on the glass I had to use a razor blade scraper. Invariably I nicked the silicone a couple times although barely so. When I fill it again I’ll do it really slow and check for leaks the whole time. So to what degree did you nick your silicone relatively speaking?