Review on 2-Quart Bio-Filter Media for Marine and Freshwater Aquariums, 1.5-Inch Sphere by Heather Joseph

This is my second box for my BioCube 14 to which I have added a 10 gallon sump. So I have a gallon of it in the sump which the manufacturer says lasts 500 gallons. My tank is tested for zero ammonia, nitrite and nitrate levels. I only did a water change after the first pool cycle in February. I feed three chromis a day with a cube of frozen food and I have yet to register nitrates in my test kits. I know Refugium helps Heto, but I know these balls work.