i fully agree with manjeet that we can put reed switches and a small float and had even thought about it ... but you see a Rs. 3/- (13 cents if i not wrong in the conversion) Stainless steel Nut bolt cost much lesser than the reed switch and the float...
thanks a lot for all the suggestions .... still working on it ....
will let you know soon if i made it work completely ....
love to all
nitin