We present a study of the effect of wet etching on the magnetic properties of two different GaMnN epi-layers. In both samples, X-ray diffraction scans revealed peaks attributed to secondary phases prior to etching and the disappearance of these peaks after etching. Temperature dependence of magnetization revealed a magnetic transition at approximately 170K in both samples. Both exhibited magnetic hysteresis, one up to 300K and the other only below 170K. After etching, the first sample still exhibited hysteresis up to 300K, and the other exhibited no hysteresis. Neither sample showed the magnetic transition at 170K after etching. A secondary phase with a Curie temperature near 170K may be responsible for the observed effects.