Hey! Mangesh, 

Nobody add anything to boiled liquid, it is common sense. Why to follow unnecessary things that are not suppose to do and ask questions in RG. Simply follow how to make. Once you add Agarose to the buffer mix thoroughly by gentle shake then boil, it completely dissolves cool under water pour it and caste gel without air bubbles (boil thoroughly Agarose without single flake by adding to buffer before).

Good Luck!!!