Here in SW Florida, the roots of the wild bermuda grass growing over my drain field has clogged the perforated pipe several times... I am considering just removing all the grass and putting gravel of some sort over the whole area and using potted plants as landscape material... essentually creating a patio feel... the question is, should I put down a weed barrier (thick plastic, landscape fabric etc. ) under the gravel or will that interfere with the function of the drain field?