Why tanker fills dirty a tank faster
A tanker fill is a sudden, strong inflow. It stirs any sediment on the tank floor and can carry fine particles from the delivery tank itself, so the water may look cloudy right after delivery.
With a network line the flow is slow and steady, which disturbs the floor far less. That is why many tanker-fed tanks are cleaned on a shorter cycle than network-fed ones.
If you receive tanker water most weeks, assume your sediment build-up is faster than average and use the frequency guide on this site as a starting point, then shorten it based on what you see.
