I always appreciate advise and constructive criticism. Especially when i am making a mistake that i can learn from. It appears that my photo did not do the best job at showing that he was indeed being kept in shallow water. Changed every 2 days or so. About 3/4 of an inch or so. To shallow to drown in.I'm going to mention what I see wrong in that picture, not to hurt your feelings or pick on you, but to offer a suggestion as to why he died.
Because baby box turtles are so very, very small, they dry out quite quickly. They need to be kept in very moist conditions. Not just soaking and access to water, but moist substrate and maybe leaf litter to hide under. I don't see any substrate at all in that picture, just a bare, glass floor. My baby box turtles live is swamp-like conditions and you can actually see water standing in several places around the enclosure.
I'm so very sorry you lost little Bauri. They are beautiful box turtles and quite entertaining to keep.