Usually I find the answers to my questions in the archives here but oddly, not this one. (or I'm searching for the wrong wording)

But my male BP which is 5 months old usually has normal looking poop, but this week his poop looked very chalky and crumbly. He's got plenty of water, ate 6 days ago just fine, his temps are good, but at night they drop to 75F. I'm already working on getting him into a tub (tomorrow). Ideas?