Have algae appeared in your tank?

Razrast alg v IBC cisterni

The growth of microorganisms is first visible on the inner walls of the tank. It can appear green, brown, or even pink in color.

This is a very common problem with IBC tanks used for rainwater harvesting or outdoor water storage. The good news is that algae can be prevented very effectively – without chemicals and without replacing the tank.

On this page you will learn:

  • why algae form in the first place,
  • which solutions actually work,
  • and which products to choose based on your use.

Why algae form in an IBC tank

Algae (microorganisms) need only four things:

  • light (sunlight or daylight),
  • water,
  • heat,
  • food.

IBC tanks are often:

  • white or translucent,
  • postavljene na soncu,
  • with openings that allow light to enter,
  • not equipped with rainwater filtration.

This means that the conditions for algae growth are ideal, especially in spring and summer.

⚠️ Important:
Once algae start to grow, they are harder to remove than to prevent.

Why algae are a problem (not just aesthetic)

The presence of algae can cause:

  • clogging of valves, pipes and filters,
  • poor water flow,
  • unpleasant odor,
  • lower water quality for irrigation,
  • more maintenance and cleaning.

That is why prevention is always the best solution.

The most effective solutions to prevent algae (the biggest impact for the smallest investment)

✅ Solution 1: Protection from light – TARP cover

The most important step in preventing algae is complete light blockage.

👉 IBC TARP cover:

In 8 years, we tested 14 different tarps made from various materials and price ranges.

The TARP tarp in Slovenia’s weather conditions wins in every aspect:

  • Se ne strga – za razliko od ponjav iz folije
  • Stops UV rays – UV rays do not reach the tank, keeping the plastic tank flexible, which is essential for long-term use.
  • Does not become brittle and does not crack.
  • Actually darkens the inside of the IBC tank (completely blocks sunlight from passing through) – low-cost tarps often only cover the tank, while a lot of light still passes through them, so the effect is practically nonexistent.
  • Reduces water heating.

Why it works:
Without light, algae cannot grow.

Advantages of the cover:

  • immediate effect,
  • without chemicals,
  • long service life,
  • easy installation,
  • also protects the tank from UV rays,
  • the water stays cooler during the summer months.

Here we present our TARP cover, which offers the best balance between quality and price. Our test unit has been in use for 6 years under full exposure to weather conditions.

It is coated with a PVC layer, making it UV-resistant.

The woven material makes it robust and tear-resistant, unlike thin foil covers.

It is equipped with openings at the lid and the valve for easy access. They can be opened and closed using Velcro fasteners.

Tarpaulin TARP for IBC tank

An excellent volume discount is active. The discount is applied automatically in the cart.

129.50€
2 – 326.55€
4 – 923.60€
10 +20.65€

29.50€Add to cart

✅ Solution 2: Basic filter – 3D AquaMyst

👉 3D AquaMyst filter

Even if we prevent algae growth, the following can still enter the water:

  • dirt particles,
  • organic debris,
  • tiny algae particles.

That is why basic filtration is the second key step.

3D AquaMyst filter:

  • filters mechanical impurities down to 0.2 mm,
  • improves water quality,
  • protects valves, pipes and connections.

Why it matters:

  • prevents nutrients from reaching microorganisms,
  • extends the lifespan of the tank,
  • The displayed filter is certified for food contact, unlike similar filters,
  • it can be easily emptied and cleaned,
  • even when full, water does not stagnate,
  • over time it needs to be replaced – depending on site conditions. We usually recommend two filters per year.

It is suitable for IBC tanks with an opening size (DN150) – the actual hole in the tank has a diameter of 140 mm.

3D AquaMyst maps of the IBC tank

An excellent volume discount is active. The discount is applied automatically in the cart.

117.50€
2 – 413.50€
5 +11.50€

17.50€Add to cart

Recommended combination (best results)

💡 Najboljši učinek dosežete s kombinacijo obeh rešitev:

  • the cover prevents algae from forming,
  • the filter prevents nutrients from reaching microorganisms in the water, thereby inhibiting their growth.

This is:

  • a long-term solution,
  • with minimal maintenance,
  • without modifying the tank,
  • at an unbeatable price.

Additional filtration and inlet options for your tank (optional)

If you want to further improve the system or automate the rainwater inlet, you can also check out:

👉 Drain filters for IBC tanks

👉 TritonFlex© filter – choose the lid, seal, filter and matching reducer for your IBC tank. Our patented solution for complete rainwater sealing and filtration in IBC tanks.

FAQ

Do I need to remove algae before use?

If the growth is already strong, it is highly recommended to clean the tank.
If the algae are still in an early stage, installing a tarp and a filter can stop the problem before it gets worse.

Are chemicals required?

Ne. Pri zbiranju deževnice se kemikalije ne priporočajo, še posebej za zalivanje. Mehanske in pasivne rešitve so boljša izbira.

Does the tarp also work in winter?

Yes. In winter, algae are not active, but the tarp also protects the tank from temperature fluctuations. We also offer a wide range of thermal and heating covers.Browse our selection.

Not sure what to choose?

If you are not sure which solution is best for your IBC tank, you can contact us.
We will be happy to help you choose the right combination.

More about IBC tanks → IBCINFO

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