Answer: Cacti prefer an extremely well-drained soil that is not overly rich. As houseplants, they may get by on a thorough watering once every 3-4 weeks, but if overwatered the roots can rot and the plant eventually dies or rots, also, which may be why your plant is "droopy." When you say the soil is hard, I wonder if the water is just running down the sides of the pot and out the drainage holes before the plant roots can absorb it. You might consider repotting your cactus. Try to find a soil specially made for cactus or mix about 1/3 potting soil, 1/3 vermiculite, and 1/3 tiny bits of rock to improve drainage. Hope this info helps!
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