Left: water 氵, right: new moon 朔 (The disobedient 屰 moon 月 is not shining at new moon) [disobedient 屰 = A plant's 艹 shoot 屮 that grows crooked is disobedient.]
Mnemonic
(The moon is between sun and earth and can cause spring tides:) The water at new moon can flow upstream.
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