Bill I would not do that. What would happen is the granular fertilizer at water's edge would not go into solution in the water but would dissolve, spread out nearby and affix (bond into)into the soil at that location and encourage emergent plant growth in the spring from the bottom. That is why all pond manuals I have seen say if you are going to use granular you must not let it come in contact with the pond bottom (use platforms or other methods). I will try to find a jump start method I provided Frank some time back when he was starting shad. It is a method that works for us along the lines of what Greg stated above.

What is your alkalinity? If low then add lime now.