When I made the move to put Edelbrock Heads on my cast Iron block, I wanted to decrease the risk or electrolysis. I bought a sacrificial anode that doubled up as a radiator cap ($19). I have had the cap on my 4 core OEM radiator for 2 years now...last summer...It wasn't how it is pictured below....the thinner version is the one I just installed on my buddy's Roadrunner. You can see the before and after...is this the normal course for magnesium anodes? I thought they get eaten up, I wasn't expecting it to balloon up in size.

Is something funky going on here or is this normal?