One of the main problems in micro irrigation system is inappropriate combination and in some cases inappropriate performance of filters and sand tanks in central control systems which cause reduction in efficiency of system and increasing of operating costs. This study evaluates affect the amount of algae on the performance of disc filters sand tank in research farm deputy of soil and water and agriculture industry of Karaj. Experiments were carried out in four treatments, the first option is typical disk filter and sand tank, the second option involves sand tank automatic disc filter, the third option involves automatic disc filter without sand tank and eventually the fourth option involves typical disc filters without sand tank. These treatments have been compared in the three physical qualities of water. The results of experiments which lasted for three months showed that thattypical disc filters and automatic in organic and suspended solids concentration of less than 50 milligrams per liter, had a very good performance. Disc filters in concentration of organic matter and suspended in the range of 50 to 100 milligrams per liter, good performance. Concentrations above 100 milligrams per liter disk performance drastically declined and the sand tank are required.