sentences:  The growing fish population has prompted the city government to launch a new program to control their number.The city issued "Ordinance 004, series of 2007", launching "Janitor Fish Eradication Drive" in the City of Marikina, granting cash incentives to participants, appropriating annually fifty thousand Pesos ( for the purpose.A scientific study of the species found in five locations in the Laguna de Bay tributary system, including the Marikina River, revealed that the specimen of janitor fish previously reported as "Hypostomus plecostomus" actually belong to the genus "Pterygoplichthys", family Loricariidae.