I bought this product to condition my water and remove some ammonia that I tested thats in my aquarium. Anyways I have a 20 gallon fishtank and do 25% water changes weekly. How much do I use to dose 1 gallon jugs? It says on the bottle only does in higher amounts of water(10 gallons or higher). Also there is no way to do drops because the liquid has a seal and only pours out. Online I seen to use 2 drops per gallon. Thanks for any help