you could add some fish to your water reclamation tank for a small aquaponics system. Grow a few plants to feed the fish and this forms a closed system. There is no need to fertilize, the fish do it for you! Permaculture at its finest!
Aquaculture is the symbiotic cultivation of plants and aquatic animals in a re-circulating system. “Break-Through Organic Gardening Secret Grows You Up To 10 Times The Plants, In Half The Time, With Healthier Plants, While the "Fish" Do All the Work.