What changes the cleaning answer
Empty, wash, rinse well, dry or refill, and return clean bowls daily. Keep spare bowls so swaps are easy.
Water bowls need extra attention
Birds dunk food, bathe, drop debris, and create film that may not look obvious from across the room.
Fresh food bowls should not sit
Wet vegetables, fruit, egg, or soft foods need prompt removal and washing after use.
Place bowls thoughtfully
Keep bowls away from high perches and favorite poop zones when possible.
Best default
Clean bowls daily, change water daily, and wash sooner whenever the dish is dirty.