Seezdah Bedar is the last holiday of the long Norooz break and is a day filled with relaxation and fun outdoors. Seezdah means 13 and Bedar means away or outside. Iranians consider 13 to be an unlucky number and so for this reason, they spend the 13th day of the New Year outside the home. Seezdah-Bedar is in essence a national picnic that is celebrated with everyone going to parks, hills and mountainsides to spend the day with nature, wishing the evil spirits away. This way one hopes to avoid that any bad incidents that may occur.
More importantly, the sabzeh (sprouted wheat or lentils) is brought from the sofreh Haft-Sin to be thrown in a flowing stream or creek. It is believed that the sabzeh, which has by this time turned a little yellow, symbolizes sickness and problems. Therefore, it is thrown and carried away by the stream.and let red fish go in the rivers.
In addition, Seezdah Bedar is a big day of hope, and people who wish for things follow the tradition of tying grass together. For example if a young girl wishes to find a husband in the coming year she will tie grass. There are various chants for people who wish to get a job or be healthy or wealthy and so on. At the end of this day, the haft sin may be cleared away and families return to work.

hi thanks well done.you 'd better say GOLD FISH rather than red fish.