finding small punctures when water is limited
 

conventional way of finding punctures is to fill tube with air and submerge in bucket of water alternative remove valve pour small amount of water into tube replace valve and pump up with air rotate tube untill you find where water is escaping

I usually 'scan' the pumped up tube with my lips hoovering above the surface at about half a centimeter. lips are very sensitive and pick up the escaping air easily. On a bicycle tyre, this works out faster then getting a container filled with water, ... .

Rob