the GE II i used says "100% silicone". it always has (have used it for YEARS on FW tanks). only now with the new packaging, it also has mildew resistant properties (STILL SAYS 100% SILICONE). i had issues with my tank, am having issues with my corals, is it the GE II or because this is my first salty tank... IDK? my corals are alive... has been running with this silicone for almost a year now.

Then they are obviously falsely advertising it in that case. Probably same case as mcdolands "100% beef"

that WAS "100% ALL BEEF" patties... and there was a trade mark symbol after the "all beef" because years ago the company that made those patties for mcdonalds was called "ALL BEEF (tradmark)" therefore they were 100% All Beef patties... not false advertising. as for GE in this case, i really dont know. their just out to get us...

It's just wording. All the beef in their patties came from cows. 100% of it. All the silicone in the tube is pure silicone. 100% of it. The other stuff however is neither beef nor silicone.
Personally, over the years I've used both I and II, but the last year or so has seen a lot of people having trouble after using it. Good enough reason to rethink it and use a product that is known good.

I just used ge 1 a month ago with no problem. Blue and gray bottle. Says its for windows and doors

K I'm at Rona right now.

Ge silicone II :

Premium waterproof has mildew protection
Window & door does not say it has mildew protection
K/B supreme says 10year mold free protection


So looks like the blue/brown tube is still good

The 100% Silicone part also has to do with whether or not there is any acrylic in the caulk. Acrylic will shrink; Silicone doesn't. It can be an important factor depending on the application.

I did a tone of research on this a while ago, even email GE & was informed that ALL the silicone has traces of the mildew inhibitor in it now EXCEPT there GE SCS1200. There still may be some tubes out there in stores that don't have it but why chance it just use the SCS1200.

I am not being a smart a$$ but just can't understand why not just use aquarium silicone? Is it that much of a difference in price that you would risk time and effort just to save a few bucks?