its oxytetracyclin hci it says 10 grams in the packet and I mixed 1/4 tsp in a quart of water also mixed in about 1mg of vitamins and electrolyte mix in there too @casportpony
The 800 mg per gallon dose is should be 1.5 *tablespoons* per gallon, so I think you weren't giving enough. Additionally, oxytetracyline should not be given with some vitamins, so that could also be the reason why it didn't work.
-Kathy