I've used GE Silicone #1 (Window and Door) without a problem. Silicone II is for tub and tile. If I am not mistaken, Silicone II is marketed as mildew-resistant, which will be lethal to fish.
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Let every nation know, whether it wishes us well or ill, that we shall pay any price, bear any burden, meet any hardship, support any friend, oppose any foe to assure the survival and the success of Liberty -JFK