I have been working with the Horse Tonic supplements for almost 2 years now. I can say that my horses never run out of energy as they have their tonic and never have stomach problems since they have the ph. I have also tried the Zen on a very complex mare and have had great results… I would also like to point out the Artico which is a joint supplement and which I am already giving to the young horses to promote bone support and tissue development.