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How and When to Clean Your Plastic Storage Tank

How and When to Clean Your Plastic Storage Tank

Proper care and maintenance of your water storage tank is crucial to keeping it sanitary for the long term. Whether you're using it for potable water, irrigation, or other purposes, ensuring your tank stays clean will help keep the water safe and free from harmful contaminants.

If you're using your storage tank for drinking water, frequent and thorough cleaning becomes even more important to prevent any health issues. Factors like the color of your tank can influence how often it needs cleaning. For example, translucent or lighter-colored tanks allow more sunlight to pass through, which can lead to quicker algae growth compared to dark green or black tanks. These lighter tanks can become a breeding ground for bacteria and algae, leading to unpleasant odors, bad taste, and potential health risks.

The good news is that cleaning your water tank doesn’t have to be a daunting project. By keeping an eye out for sediment, algae, or any other unwanted growths, you can ensure that regular cleanings are just routine maintenance rather than dealing with a larger sanitary emergency. Most people can handle basic tank cleaning themselves—you just need the right equipment, access to the tank, and a bit of time to make sure every part of the interior is scrubbed and rinsed thoroughly.

In this article, we'll cover how often you should clean your water storage tank, the equipment you'll need, and the step-by-step process to make sure your tank is safe enough for drinking water. With the right care, your tank will be sparkling clean and ready to use!

Why Is It Important to Clean My Water Storage Tank?

Routine maintenance of your water storage tank includes draining, cleaning, and disinfecting it, which is essential for keeping stored water safe to drink. Even if your water looks clear, all water contains some amount of sediment that can accumulate in the tank over time. Regular cleaning helps remove sediment, algae, microbial growth, and debris, ensuring your stored water stays safe and of high quality.

Cleaning your water tank also improves the appearance and taste of the water. Homeowners are responsible for making sure their tanks are cleaned and disinfected at least once a year, or more frequently if needed. The primary goal of cleaning is to effectively wash, scrub, and disinfect the water tank, removing any bacteria, algae, or silt that has built up over time. 

Whether you have a small 100-gallon rain barrel tank or a large 15,000-gallon vertical water tank, regular cleaning is crucial to ensure it operates properly and is ready for use when needed. Keeping your tank clean helps maintain water quality, making it suitable for its intended use—especially for drinking water.

Water tank cleaning and maintenance also extend the tank’s lifespan and help detect potential problems early. Consistent upkeep makes cleaning more manageable and prevents more serious issues later on. Neglecting your water tank will ultimately result in poor water quality and more intensive maintenance down the road. By cleaning your tank regularly, you can ensure that your water stays clean, safe, and ready for use.

How often should you be cleaning your tank?

Water storage tanks should be drained, cleaned, and disinfected at least once per year. However, in areas where the water supply has high sediment levels at certain times of the year, you may need to clean your tank more frequently. If your household water starts to taste, look, or smell unusual, it’s a clear sign that it’s time to clean your storage tank.

The cleaning frequency will also depend on factors such as the size of your tank and the amount of algae or silt that has built up since the tank was first used or last cleaned. For non-potable uses—such as washing vehicles, irrigation, or supplying toilets and laundry—cleaning your tank once or twice a year should be sufficient. Even if the water isn’t meant for drinking, keeping your tank clean is important to avoid a buildup of bacteria, algae, sludge, and other undesirable debris.

For potable water tanks, it’s advisable to clean them two to three times per year. In most cases, you can take care of this cleaning process yourself without the need to hire a professional. Additionally, it’s important to have your potable water system inspected on a semi-regular basis to ensure it remains free from dangerous contaminants and the water stays safe for consumption.

You should also inspect your tank if it hasn't been used for an extended period and you’re planning to use it again, or if it hasn’t been drained for some time. Regular inspections and cleanings help maintain the quality of your water and prevent any unexpected issues.

Type of Water Tank Cleaning Frequency Notes
Non-Potable Tanks 1-2 times per year Used for irrigation, vehicle washing, toilets, and laundry. Cleaning helps avoid buildup.
Potable Water Tanks 2-3 times per year Includes drinking and cooking water. More frequent cleaning ensures water safety.
High Sediment Area Tanks More frequently as needed Areas with high sediment may require additional cleaning to maintain water quality.
Unused or Idle Tanks Before use Inspect and clean before using after extended idle periods to ensure water quality.

 

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For potable water tanks, you'll want to look into cleaning it 2-3 times per year. In most cases, you'll be able to take care of the cleaning process yourself and won't need to hire a professional.

It's also important to note that for potable tanks, you'll want to have your system inspected on a semi-regular basis. This can keep you safe from dangerous contaminants and keep your water safe enough to consume.

You'll also want to inspect your system if it hasn't been used recently (and you're looking to use it again) or if it hasn't been drained in some time.

What should you use to clean out your storage tank?

Most of the supplies you need to clean your water storage tank are likely items you already have at home. Here is a combined list of the essential cleaning tools and materials:

  • Water (at least two gallons)
  • Unscented liquid bleach (non-fiber guard)
  • Disposable gloves
  • Eye protection
  • R95 rated respiratory mask with carbon filters
  • Scrubbing tool or mop (with a sponge/scrubber head, adjustable rod for hard-to-reach areas)
  • Bucket
  • Pressure washer (optional)
  • Pump or wet vacuum (optional)
  • Sump pump, shop vac, wet/dry vacuum, or dry towels (optional)
  • Chlorine test strips (optional)

To create a bleach solution for cleaning, follow the recommended guidelines for sanitization purposes. Generally, mixing one tablespoon of bleach per gallon (3.7 L) of water is enough to effectively clean the tank while remaining safe for use. Preparing two to four gallons of this bleach solution beforehand will help ensure you don’t run out during the cleaning process.


Depending on the size of your tank, scrubbing and rinsing the interior with the bleach solution will typically be enough to ensure proper sanitization. For larger tanks, you may want to use a pressure washer to speed up the process or use a pump or wet vacuum to assist with draining the tank. For smaller tanks, these additional tools are usually not necessary.

 

It’s a good idea to prepare the bleach solution before starting the cleaning process. Mixing one tablespoon of bleach for each gallon of water works well—having three to four gallons of the solution will make sure you have enough to complete the job. By using the right tools and following the proper procedures, you can effectively clean your storage tank and ensure the water is safe for use.

What's the best process for cleaning your tank?

Cleaning a water storage tank involves multiple steps to ensure it is thoroughly disinfected and safe for use. Here’s a step-by-step guide on the best process for cleaning your tank:
  1. Drain the Water Tank: Start by fully draining your water tank. For large tanks, ensure you’re draining into a location that can realistically handle a large volume of water. You may need to use a pump or wet vacuum to remove excess water that won't fully drain. For smaller tanks, this typically won't be an issue.
  2. Scrub the Interior Walls: Use a scrubbing tool or a pressure washer to clean the interior walls of the tank. Your goal is to remove as much of the built-up grime, algae, and debris as possible. If you’re struggling with stubborn buildup, using a mild abrasive like baking soda can help. Larger tanks may require a long-handled mop with a sponge head or a pressure washer to effectively reach the top and corners. Be diligent during this stage—the tank should look almost-new when you’re finished scrubbing.
  3. Rinse and Drain the Tank: Rinse the tank with clean water to remove the loosened grime and any leftover cleaning materials. Make sure to be thorough, getting rid of as much dirty water as possible.
  4. Clean with Bleach Solution: Use a bleach solution (1 tablespoon of bleach per gallon of water) to clean the interior. This is where your gloves, mask, and eye protection come in handy. Scrub the tank walls with the bleach solution, ensuring you cover all surfaces to properly disinfect the tank.
  5. Let the Solution Sit: Allow the bleach solution to sit in the tank for at least two hours. This waiting period is crucial for killing any remaining bacteria or other contaminants that may be present.
  6. Rinse Thoroughly: After letting the bleach solution sit, rinse the tank thoroughly with clean water. This is particularly important for potable water tanks. Ensure all bleach is removed, as bleach can be harmful if ingested. Check for any soapy quality or bubbles—keep rinsing until the water runs completely clear.
  7. Test Chlorine Levels: Use chlorine test strips to measure the chlorine levels in your tank before refilling it with water. It’s essential to ensure no bleach remains in the tank. If the chlorine levels are still high, continue rinsing until you achieve a safe level.
  8. Rinse Again if Necessary: If the chlorine test indicates high levels, rinse the tank again thoroughly. Use hot water if possible to help remove any remaining traces of bleach.
  9. Refill the Tank: Once you’re confident that the tank is clean and all bleach has been removed, refill it with potable water. Your tank is now ready for use!

Water Tank Maintenance Tips to Keep Your Tank Cleaner for Longer

Proper maintenance can help keep your water tank cleaner for a longer period, reducing the frequency of deep cleanings. Here are some tips to help maintain your tank:

  • Install a Tank Cover: Ensure your water tank is always covered with a secure lid to prevent dirt, leaves, insects, and other debris from entering the tank.
  • Use a Sediment Filter: Install a sediment filter to prevent sediment buildup inside the tank. This can help reduce the amount of debris that enters the tank and helps maintain water quality.
  • Position Your Tank Wisely: Place your tank in a shaded or partially shaded area to reduce the amount of sunlight exposure. This helps minimize algae growth, especially in lighter-colored or translucent tanks.
  • Regular Inspections: Conduct regular inspections of your tank to identify any leaks, cracks, or buildup. Early detection of these issues can prevent major problems later on.
  • Clean Gutters and Inlet Pipes: If your tank collects rainwater, make sure to regularly clean gutters and inlet pipes. This helps keep leaves, dirt, and other debris out of your tank.
  • Add Screens to Inlets and Overflows: Use fine mesh screens on all inlets and overflow outlets to keep insects, debris, and small animals out of the tank.
  • Remove Sediment Regularly: If you notice sediment buildup at the bottom of your tank, consider removing it before it accumulates too much. A wet vacuum can help with this task.
  • Monitor Water Quality: Keep an eye on the water quality by monitoring changes in taste, color, or odor. This can alert you to potential contamination or issues before they become major problems.
  • Consider a Water Treatment System: For potable water tanks, consider installing a water treatment system to maintain consistent water quality. This may include UV filters or chemical treatments.
  • Maintain the Surrounding Area: Keep the area around your tank clear of debris and vegetation. This reduces the likelihood of pests or contaminants entering the tank.

 

By following these maintenance tips, you can keep your water tank cleaner for longer, ensuring that the water remains safe and suitable for use.

Conclusion

Maintaining your water storage tank is essential for ensuring the safety and quality of the water it holds. Regular cleaning, proper maintenance, and following the best practices outlined in this guide will help keep your tank in optimal condition. By taking a proactive approach to cleaning and maintenance, you can extend the lifespan of your tank, prevent health risks, and always have clean water ready for use. Remember, a clean water tank means healthier water for you and your household.

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