I just bought to 2 geophagus from local fish store. I have 14 discus in 120g tank. My discus are 4-6" but somehow they are showing stress. I will give a few weeks.
Did you add the geo's without QT with the discus? Would suggest a 50% daily water change for a week and see if that helps.
Pat
Your discus are talking to you....are you listening