National Biotech W e began our operations under the business name National Bio Tech about 10 yrs ago as an effort to conserve nature's precious resources. Our plant is situated in Vasai City, about 30 kms from Mumbai and is spread in an area of about 5 acres.Vermiculture positively addresses waste management issues and soil fertility. Two pounds of worms, approximately 2000 of them, will eat one pound of compost every 48 hours. Earthworms excrete a highly nitrous fertilizer (called castings), which contain five times the available nitrogen, seven times the available phosphorous, three times the exchangeable magnesium, eleven times the available potash, and 1.5 times the calcium found in 6 inches of topsoil.