Photocatalytic conversion of nitrogen to ammonia is a green alternative for the Haber-Bosch process. The current progress in photocatalytic nitrogen reduction suggests, however, that there exists a large gap in performance before commercial use is viable. One of the major challenges is that no highly active photocatalysts exist. Furthermore, the development of photocatalysts is greatly hindered by false positives or non-reproducible data. Here, we will describe the current known causes of non-reproducible results in the literature and present solutions to mitigate these false positive results. Finally, we highlight the main challenges that remain for photocatalytic nitrogen fixation. We aim to help researchers design more reliable experiments and inspire practical research in developing photocatalytic ammonia synthesis.