Mr. Wak Songprasert 212 Moo 6 Bantayom Tumbon Wattayom, Bangkratum District, Pitsanulok.
He has three fish ponds, in the area of three rai/4800 square meters, so one pond is about one rai (1600 square meters), there were 100,000-200,000 catfish. Before using EM he used chemicals and microorganisms which he bought from the market. He did not profit because of the high capital outlay. Sometimes he had a deficit. In 1994, he began to use EM in his pond.