Earth and water nourish each other naturally: water softens earth and earth gives water a course. Among the most harmonious combinations — mutual care, home, depth. Your task: don't close off so much the bond becomes a bubble.
One holds steady (fixed), the other flows (mutable): the fixed one gives the mutable roots, and the mutable teaches the fixed that changing isn't losing. Complementary — as long as neither caricatures the other as 'stubborn' or 'flaky'.