Manufactured by Thetford, the economical Activ range has the same advantages as the Thetford Aqua products, use a similar dose, but are effective for a slightly shorter period..Add 75ml of activ Blue per 10litre of waste tank holding tank capacity plus 3 litre of water.• Safe to empty in septic tank • Lasts 2-3 days with average use • It remains liquid up to -20° and remains active after defrosting. Use 70ml per 10 litre of flush tank capacity. Provides a more effective flush and keeps the flush water fresh. Leaves a protective film in the bowl that prevents deposits from forming. The lubrication action makes the blade of the waste holding tank easier to open and close