It's always better to give the clues - people without a copy of the crossword can, and do, help.
13 A. Wading bird, one coming ahead of the cold wind (4)
Ibis, wading bird. I = one and Bis(e) is a wind.
18 A. Antiseptic only rejected around America (5)
Eusol - Sol(e), only +US, America.