A little confusion with this product. When you do say a 20-25% water change do you have to do the math a figure out approx. how much was removed or do you add enough to treat the entire volume of water?
For instance I have a 90 gallon tank do I add enough to treat 90 gallons or do I add enough to treat say 18-23 gallons? the instructions are not real clear? :headbang2:
For instance I have a 90 gallon tank do I add enough to treat 90 gallons or do I add enough to treat say 18-23 gallons? the instructions are not real clear? :headbang2: