I think there's something up with him. I did a minor w/c last Thursday before I left town for Thanksgiving. I gave both my bettas a small freezedried bloodworm and a pellet.
I got back on Tuesday night, and Othello was pretty pale and inactive. It was late at night, though, so I thought he was probably asleep.
Next day, he was still pretty pale...fairly active though, and ate.
Thursday, I did a 50% w/c...he spent most of the day hiding, not active...still ate after a while in his cup.
Today, he's also hiding, and he's looking more gaunt/thin...still pale. He didn't eat his bloodworm either.
My tank is 10 gallons, split in 3 between my three boys. The heater hasn't been working so well lately, it keeps the water around 73-75 degrees...I think that may be a reason of why he's been weird lately.
PH and other water parameters are normal.