Fisk Tech Services:

Underwater Maintenance

Fuel Efficiency. Decarbonization. Green Transition. Commercial Efficiency.

Underwater maintenance is a crucial part of fleet management, both for the preservation of your business assets and to minimize operating costs. Fisk Tech employs a diverse maritime skillset to ensure your commercial needs are met.

“Added Resistance” describes the reduction of hull and propeller performance of the vessel due to biofouling, which means that its ability to achieve the desired service speed at CSR (Continuous Service Rating) of the main engine, is reduced.

Rule of thumb is that a 1% loss of speed at CSR equates to a 3.5% increase in fuel consumption. With added resistance comes a cost to the environment with additional carbon emissions, as well as a surcharge to the OPEX (operational expenses), hitting the financial bottom line of a ship owner.

At Fisk Tech our extensive experience helps us understand your business. Utilizing the latest technology, our talented team produce proactive solutions for your operational and commercial needs. We work with you as a partner, building a relationship that aims to bring you the highest service standards, efficiency, and results.

Propeller Polishing

The propeller is the driving force of your vessel and the only unprotected part of the hull. Polishing the propeller every 6 months equates to an approximate saving of 1% on fuel and a 0.5% increase in speed – both commercially important factors when getting your ship to its destination.

The Fisk Tech team gives your vessel’s propeller the attention it needs. We also inspect your hull at the same time. Through our experience, we also recommend that the propeller is cleaned in‑water before the ship enters a drydock to give a softer “pre-clean” before she is on the blocks.

Hull Inspection & In‑Water Surveys

This is the most proactive way to validate the performance of your hull and plan the next steps to maximising the output of your vessel.

We look closely at your hull and put together a report that includes analysis by our in-house naval architect. This holistic viewpoint ensures that accurate advice is provided by our team.

Depending on the situation, we deploy experienced divers or a Remote Operated Vehicle (ROV) to ensure a thorough inspection. Our in-water surveys are Class Approved.

Hull Cleaning

Effective hull cleaning is a solution that returns up to 14% savings on fuel, improves speed performance by 2-4%, and reduces a ship’s annual CO2 emissions by as much as 20%.

Operational experience tells us that hulls should only be cleaned ideally after the 2nd year from a drydocking and completed once per year. Unlike other less effective solutions, Fisk Tech utilizes the latest in brush kart technology to provide this optimal solution.

Latest studies have concluded that frequent hull cleanings only lead to a law of diminishing returns, meaning that the more frequently a hull is cleaned, the costs of cleaning outweigh the benefits1. This means that alternative solutions such as hydro cleaners are less cost effective over time.

We only use brush karts to clean your hulls. Over 2000 hull cleanings show that it is a flexible solution that adapts to the condition of fouling. Suspension brush heads, with bristles ranging in toughness that effectively work on both soft and hard biofouling, give a fine clean that gets your anti-fouling reactivated.

This solution also prevents frequent cleanings as the antifouling gets a much needed rejuvenation. And as a bonus, we reach all the niche areas of the hull!

1. Danish Technical University, 2018

Fisk Tech's hull cleaning solution could reduce a ship's annual CO2 emissions by as much as 20%.

Our Process


At Fisk Tech we believe in a collaborative approach to the services we supply. We are constantly looking for ways to add value to the wider ecosystem, to collaborate and co-create with organisations in the ecosystem.

Get in touch with the team for more information on this approach and how we can work together.