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Why is my VirtualTank Showing a Negative Volume?

Modified on: Thu, 3 Jul, 2025 at 3:19 AM

Tanks FMTData
Harrison Court By Harrison Court
A VirtualTank calculates its levels by subtracting the dispenses done on a mapped pump, and requires manual dips or manual deliveries to be added onto that tank to keep the levels accurate. 

If your tank is showing a negative value, the most likely reason is because the tank has calculated the dispenses mapped to that pump, but no-one has added in any deliveries or a manual dip onto the tank, allowing the tank volume to fall into a negative number.


The quickest way to resolve this issue is to add any missed deliveries onto the system, and add a manual dip afterwards.

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