# Tanks, dip charts and the morning dip — Octyn Help

> Set up fuel tanks and dip charts in Octyn, record the morning dip with water and density, and read daily stock variation.

Canonical: https://octynerp.com/help/tanks-and-dips

# Tanks, dip charts and the morning dip

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Set up fuel tanks and dip charts in Octyn, record the morning dip with water and density, and read daily stock variation.

Video **9 min** Updated **14 October 2026** For **Owner, manager or cashier** Tutorial **18 of 39**

## 01 Set up a tank

Once per tank. The dip chart is what turns a dip reading into litres.

1.  Go to **Station setup → Tanks & dip charts** and choose **Add tank**.
2.  Pick the fuel, type the tank number painted on the manhole, and its capacity. Add the inside diameter and length — they are printed at the top of the dip chart.
3.  Tick the **nozzles** that draw from this tank. A nozzle can only draw from a tank holding the same fuel.
4.  Next comes the **dip chart**. Upload the Excel sheet or the **PDF** from your oil company, type the rows, or **Estimate** it from the tank size. For a paper-only chart, Estimate from the printed diameter and length is the most accurate.
5.  Check the rows, then type **three readings** straight off the paper chart. When all three match, the chart is saved as **verified**. An estimated chart is marked so, until you replace it with the real one.

## 02 The morning dip

Every morning, before sales and by 10 AM — the oil company expects it.

1.  On the home screen, the **Morning dip** card lists every tank. Tap one.
2.  Type the **product dip** and the **water dip** in cm. The litres appear as you type.
3.  Switch on **Density check** and enter the hydrometer reading and temperature. Octyn converts it to **density at 15 °C** and compares it with the last delivery. More than 3 kg/m³ away from the last delivery is flagged.
4.  If water is found, Octyn tells you to report it to your oil company, and the owner is alerted.
5.  Made a mistake? An owner or manager opens the dip in **Daily ops → Tank dips** and saves a correction with a reason. The first reading is always kept.

## 03 Unloading a tanker

Step by step, in the order the oil company's rules lay down. Every step saves as you go.

1.  Open the tanker's invoice in **Purchases** and choose **Unload this tanker** — or go to **Daily ops → Tanker unloading**.
2.  Check the truck: seals and locks match the invoice, and the calibration certificate is valid. A broken seal means **refuse the load**.
3.  **Stop sales** from the tank, dip it, then let the tanker **settle for 10 minutes** — Octyn counts it down.
4.  For each compartment enter the **density and temperature**. More than 3 kg/m³ from the invoice shows **Do not unload** — refuse the load and call your oil company. Only the owner can record that such a load was taken anyway, with a reason.
5.  After unloading, dip the tank again and note any **short dip** per compartment and whether you made it up. Attach a photo of the signed invoice back.
6.  Dispense **50 litres**, check the density again and **Finish**. That is the tank's new **reference density** until the next load.
7.  Everything lands in **Compliance → Density register**, in the oil company's own columns, ready to export.

## 04 Stock variation

Does the tank agree with the book?

1.  Open **Compliance → Stock variation**. Each day shows opening dip + deliveries − meter sales against the next morning's dip.
2.  Losses up to the **evaporation allowance** (petrol 0.75 %, diesel 0.25 % of sales) are expected. Beyond **±4 %** of stock the oil company treats it as an irregularity.
3.  A run of five or more days in the same direction is flagged — it usually means a leak, a meter giving short, or dips taken at different times.
4.  At month end the owner can **Accept variance** so the book matches the tank. It is posted at average cost and shows in cost of sales. The 5-litre nozzle test goes back into the tank — record it as a test draw in the shift, not as a sale.

**Done.** Dip at the same time every morning, after the tank has rested — a dip taken during or just after a tanker unloads will not agree with anything. [Open it in Octyn](https://app.octynerp.com/operations/dips).

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