This is a donation from select aquatics of Erie, CO. They put together this fertilizer themselves. Only needs to be dosed twice per month. Only one and a half teaspoons per 30 gallons of water is needed. Watch your plants transform with this fertilizer. You will receive 16 ounces of fertilizer. Please check out their website for more information on this fertilizer. http://selectaquatics.com/Plant%20Fertilizer.htm