Aquaponics is, simply integration of hydroponics (cultivation of plants without soil) and aquaculture (fish farming). In aquaponics system water from aquaculture is used as irrigation water for crop production and extra water returns back to fish tank. When this water circulated near root zone, nitrogen fixing bacteria (manly nitrosomonas and nitrobactor) convert ammonia (NH4) in to nitrite (NO2) and then to nitrate (NO3) form, which is very good source of nitrogen for plants and less toxic to fish in aquaculture system as compare to ammonia. A part from this, aquaculture water is also very good source of almost all macro/ micro nutrient required for plant growth. So this is completely self sustainable system of crop & fish production where about 90 % of the water and 100 % nutrients are recycled for organic crop production. This is an experimental setup at Vigyan Ashram and the document publishes results we have received.