Protect fuel quality and equipment with a proven tank cleaning program
The Problem: Rust and Particulate in Fuel Tanks
How rust and particulate form
Rust and particulate contamination develop naturally over time in underground storage tanks. Water is the catalyst — often entering through condensation, poor seals, or surface water ingress during heavy rain. Once water settles in the bottom of the tank, it provides the conditions for corrosion to take hold and microbial activity to thrive. Microbes living at the fuel–water interface create acidic byproducts and biomass, accelerating rust formation and generating sludge. In addition, ageing internal coatings, fittings, and pipework shed particles into the fuel stream, while poor housekeeping practices such as dirty deliveries introduce further debris.
Risks to your network
The presence of rust and particulate quickly translates into operational and financial problems. Filters clog prematurely, slowing down dispenser flow and frustrating customers. Pumps, turbines, and meter sets wear faster due to abrasive particles and contamination, resulting in costly replacements and unplanned downtime. Automatic Tank Gauges (ATGs) can give false alarms or inaccurate readings when sludge accumulates at the bottom of the tank. Over time, persistent contamination leads to reduced fuel quality, customer complaints, and reputational damage. Networks also face higher service costs due to repeated callouts, increased filter spend, and shortened equipment life.
Traditional Water Pump Outs Fall Short
Limitations of pump outs
Many operators attempt to manage water and contamination issues with standard pump outs. While this may seem like a quick solution, pump outs only remove the visible layer of free water at the bottom of the tank. The more significant issue — emulsified water suspended in the fuel — remains untouched and eventually separates out again, causing the same problems to reappear. Even more critically, rust flakes, microbial sludge, and corrosion scale clinging to the tank floor and walls are left behind.
Pump outs also come with hidden costs. Because water and fuel are drawn together, operators lose large volumes of otherwise saleable fuel during the process. This results in direct financial loss and requires the fuel/water mixture to be handled and disposed of as waste, creating an additional environmental liability. Worse still, because the contamination is not fully removed, the operator is often forced to repeat the pump out within weeks or months, compounding costs while never addressing the root cause of the problem.
The Flowco Three Stage Tank Cleaning Method
Stage 1: Precision floor cleaning
Specialised suction equipment slowly traverses the tank floor to remove free water, sludge, and rust particulate from low points and surfaces where contamination collects. This eliminates the source of corrosion and bacterial growth.
Stage 2: Fuel polishing
The entire tank volume is circulated through multi stage filtration and separation. This removes suspended particulates, entrained water, bacteria, and other contaminants invisible to the eye but harmful to fuel quality and equipment.
Tank Cleaning and Fuel Polishing Before and After Samples
Stage 3: Return of 100% saleable fuel
After filtration, the entire volume of cleaned fuel is returned to the tank in specification. Only waste water and sludge are removed for disposal. Site owners retain all usable product, avoiding the financial and environmental cost of wasted fuel.
Why This Method Works
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Removes both free water and water held in suspension
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Lifts sludge and corrosion scale from the floor and walls
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Restores and returns 100% of saleable fuel to the tank
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Reduces repeat visits compared with pump outs
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Supports compliance and best practice housekeeping
Signs You Need a Tank Clean
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Filters blocking between scheduled changes
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Slow or inconsistent dispenser flow
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Repeated water alarms after rain events
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Visible rust or dark particulates in samples
What You Can Expect
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Clear product to specification with water and sludge removed
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Reduced filter spend and fewer callouts
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Improved dispenser performance and customer experience
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Extended life of pumps, turbines, and meters
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A documented baseline for future maintenance
Frequently Asked Questions
Is a pump out enough if I just have some water?
No. Pump outs only remove visible free water. Flowco’s three stage process removes water, sludge, rust, and even emulsified water and bacteria.
Will I lose fuel during cleaning?
No. 100% of saleable fuel is polished and returned to the tank. Only waste water and sludge are removed.
How long does a standard clean take?
Most single-tank cleans are completed in a single day. Multi-tank sites and heavy contamination can take longer.
Do you provide a report?
Yes. You receive a report with findings, actions, and results for quality records.
Can you provide more detail on the process?
You can reivew the process on our Tank Cleaning page or see a great annimation of the process on our YouTube page here
