water in which rice has been washed
潘 centers on the water left after washing rice, a specific byproduct of food preparation. Its meaning is narrow and concrete, referring to that starchy liquid.
潘 combines 氵 (water) with 番, which likely contributes the sound. The character specifically denotes the water used to wash rice.
The water radical 氵 beside 番 (which can suggest a number or turn) hints at water that has been used in a process: the starchy water left after washing rice.
For ハン, imagine a hand scooping up the cloudy rice-washing water: hand -> ハン, and the water is exactly what 潘 describes.
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