Solid poops 💩

My boy is obsessed with these snacks but his poops are rock hard and I feel like these might be a contributing factor. These have zero fiber. He screams bloody murder when he poops. I give him lots of water in his bottle and sippy cup and he’s still breastfeeding. I’ve resorted to mixing his water bottle with apple juice but I’m super uncomfortable with giving him juice this early. What am I doing wrong and how can I help my angel have softer poops. His poor bum 😔