Battery Charging Problem

Help!! My SGS3 battery is not charging up. Its been an hour i have plugged in to the charger and battery life is degrading like anything. Drained from 29% to 18% in just one hour and in charging mode. Yes i am using the phone, browsing, Instagraming but the battery should not drain na.

Help.. What to do? My phone's rooted. Does that cause harm? :/

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