The Messenger of Allah [SAW] said: "Do not soak Az-Zahuw and ripe dates together, nor Al-Busr and raisins together. Soak each one of them on its own." (Using translation from Nasāʾī 5566)  

أَنَّ رَسُولَ اللهِ ﷺ قَالَ «لَا تَنْبِذُوا الزَّهْوَ وَالرُّطَبَ جَمِيعًا وَلَا الْبُسْرَ وَالزَّبِيبَ جَمِيعًا وَانْتَبِذُوا كُلَّ وَاحِدٍ مِنْهُمَا عَلَى حِدَتِهِ»