hope this mini guide helps:

1) how's the weather there? No...I'm serious. Here in Manila, it can get QUITE warm during the day, causing my pythons to stick REAL close to their water bowls (although why I haven't "caught" them bathing, eludes me).

2) how's the skin? duller than usual? the eyes cloudier than usual?

3) how long has he been with you?

4) some snakes just like water more than others; I recall my afrock who just HAS to chill out in his water bowl no matter what (even after defecating in it....eeeeew...imagine my dinner when I get home from work and the stench of his "waste water"...yuuuck!). Never kept a Morelia but I guess some species (or individual members!) tend to bathe more often than other species.

5) is he dehydrated? Here's a link to help out.

Do update us ASAP