No soil will be completely impermeable, but if the bucket is set outside so it sees rain, you shouldn't see the water continually dropping and weeping out the bottom. Ideally the water level in the bucket (with normal rainfall) will stay the same (rainfall is keeping up with evaporation).

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).