Will the water turn yellow if you put a water containing btb and crayfish or tadpole?

Yes, the water may turn yellow if you add a water solution containing bromothymol blue (BTB) to a container with crayfish or tadpoles. BTB is a pH indicator that changes color based on the acidity or alkalinity of the water. When crayfish or tadpoles respire, they release carbon dioxide, which can lower the pH and potentially cause the BTB to shift to a yellow color, indicating a more acidic environment.