Hull Cleaning

Underwater hull cleaning or ship hull cleaning is an extremely important part of maintaining the health and integrity of the vessels. You may wonder why, since your vessel seems to be in good shape. Let us elaborate on why you should consider this service.

Vessels which are used to partially residing under the surface of seawater or freshwater face various levels of fouling by marine or aquatic organisms, caused by the biofilms formed on such structures. Hull cleaning ensures that the biofilms formed, and the fouling organisms attached to all subsurface structures, including propellers, rudders, inlet and outlet ports, sonar housings, and protective grills, are removed and the health of the vessel maintained.

So, how does underwater hull cleaning help your vessel perform better and more effectively? Underwater ship hull cleaning is extremely important as hull and propeller performance may deteriorate over time, if biofouling is not cleaned routinely. This could lead to mechanical damage and the resulting poor hull conditions will reduce energy efficiency. Further, underwater hull cleaning is essential as biofilms stuck on the hull can impact the ship’s dynamics by heightening drag and the required propulsion. Studies also indicate that an idle vessel tends to gather more biofilm and, therefore, requires greater hull cleaning services to maintain its integrity.


Now that you have an idea of this service, what is the process? Hull cleaning involves the use of different machines and solutions to get rid of the biofilm and the attached biofouling agents as this helps maintain the vessel’s performance and energy efficiency over years. At present, methods such as dry-docking cleaning, antifouling paint, and periodic underwater cleaning are frequently used for underwater ship hull cleaning. Studies have also indicated that use of high-pressure abrasives in dry docks can also be a good method of underwater hull cleaning.

Hull cleaning

Nereus Subsea is an expert in underwater hull cleaning services. We offer you a variety of services in this regard, including but not limited to the following –

The most common ways include manual hull cleaning, powered rotary brush cleaning systems, and noncontact cleaning technology. The first method, manual hull cleaning, is usually performed on small ships such as recreational yachts and fishing boats. This is usually done by workers on the ship or even by the owners themselves. Based on the amount and nature of the biofouling, including slime, biofilm, etc., and the type of antifouling coating already present on the vessel, the manual hull cleaning many be carried out using cloths, brushes, or scraping devices.

The second method is the powered rotary brush cleaning system, which uses mechatronics equipment, especially for large vessels. In such scenarios, large brush devices are preferred for quickly cleaning flat or slightly curved areas of the hull, and small brushes are utilised for better results when cleaning the propeller. Bigger vessels might even choose a combination of multiple brushes for best results.

Thirdly, there is the simple cleaning tactic, where unpowered cleaning brushes are used to frequently remove deposits from the surface of ships. This is done manually and routinely to ensure that the surface remains clean and healthy. It is also simpler than the other two methods but cannot be used for larger surfaces or for harder coats of biofouling agents.

Finally, under the contactless underwater cleaning method, there are techniques like high-pressure water jet method, the cavitation water jet method, and the ultrasonic cleaning method. These methods are known to be highly effective and they cause minimal damage to the vessel, as long as they are used properly, and by experienced professionals.

As experts in the arena and armed with years of experience, Nereus Subsea undertakes a complete evaluation of your underwater hull cleaning requirements before suggesting the best method for your needs. You can trust that we have your best interest at heart, always.


Are you now wondering about what advantages you will receive from this endeavour? Well, our specialised and niche hull cleaning services help you with the following important aspects and offer you benefits such as –

  Removal of slime and biofouling – these can increase the drag and damage the hull of your ship.

  Express cleaning of biofouling growth after low activity or lay-up period – if your ship has been sedentary for a period of time, this service will help you get rid of all the biofouling agents stuck to the hull.


  Coating maintenance – the coating on your hull protects it from damage and we help you maintain it in the best way possible.

  Managing fouling at the arrival of a vessel – when your ship is ready for its voyage, it needs to be cleaned completely. We help you do this, in addition to managing patchy fouling.

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