Propspeed prevents marine plants from bonding to metal surfaces below the waterline. Propspeed works because it’s slick, not because it’s toxic.

What is Propspeed

Propspeed is a foul release coating system designed and proven to prevent marine growth like pox, sea worms, algae, and similar organisms from bonding to metal surfaces below the water line.

Propspeed was developed in New Zealand 10 years ago, and has since been successfully applied in more and more locations around the world. The system combines the ultra-smooth characteristics of silicon and the excellent bonding of two-component etching primer to ferro and non-ferro metals. Thanks to the ultra-smooth top layer – the clear coat – it is close to impossible for marine organisms to adhere to metal surfaces. The two-component etching primer facilitates a strong connection between the metal substrate and the silicon top layer. The primer adheres to all metal surfaces, and in particular to bronze, aluminium, and stainless steel.

From experience, most boat owners and boatmen know that a vessel performs at its best in the first weeks after cleaning and foul release. A less pleasant yet inevitable experience is the loss of performance resulting from gradual marine growth below the waterline. Infrequent sailing may even proportionally accelerate a vessel’s loss of performance.

Propspeed contributes to sustained performance by keeping props, rudders, and trim tabs clear of marine growth. Propspeed enhances the power transfer between running gears and water, while limiting performance loss caused by resistance. Like this, props do what they were built to do: cut through the water and convert engine power into propulsive force as efficiently as possible.

Marine growth effects on propellers and other metal parts below the surface.

Marine growth on propellers and other metal parts below the surface, like rudders and trim tabs, may lead to:

  • Increased fuel consumption
  • Loss of speed
  • Obstructive vibration of propeller shaft and related components
  • Cavitation

In case a vessel is infrequently sailed, already after a couple of months performance loss resulting from marine growth amounts to an average of 5% to 10%. Larger, infrequently sailed ships can see their performance cut by up to between 15% and 20% after 1.5 to 2 years. These are average numbers; precise data is hard to come by as individual performance depends on cruising speed, vessel size, and hull shape. In general, we can state that the higher the propeller’s rotational speed, the bigger the effects of marine growth.


Propellers push a ship forward by propelling water backwards in a spiral-shaped tunnel pattern. Marine growth quickly wears out a propeller’s efficiency, as it causes air bubbles to fill the water tunnel and disturb the propulsive pattern. This effect is known as cavitation. In addition, more strongly polluted propellers may succumb to imbalance and cause vibration, leading to increased wear of the propeller shaft bearings, propeller shaft seals, transmission, and other components of the power train.

The advantages of Propspeed

By preventing marine growth-induced resistance, Propspeed facilitates efficient power transmission from the propeller to the surrounding water mass. Resistance is cut even further when propeller shafts, rudders, and trim panels are also treated. In addition, Propspeed prevents cavitation that results from marine growth.

The use of Propspeed can, depending on vessel type and circumstances, increase maximum speed by three knots.

Decreased fuel consumption

Marine growth below the waterline and on propellers in particular, causes resistance with negative consequences for a vessel’s cruising speed. If the loss in cruising speed is compensated by additional engine power, fuel consumption rises. When using Propspeed, less engine power is required to obtain identical cruising speeds. In practice, this yields a fuel reduction of up to 10% on average, depending on the vessel and circumstances.

A long-term solution

If applied properly and if no electrolysis problem or mechanical damage of the top layer occurs, Propspeed remains active for at least a year, and in most cases even considerably longer. During this time, a vessel can be taken ashore and launched again without problems, as long as the top layer remains intact. Moreover, components that were treated with Propspeed may not be cleaned with a pressure washer.

No burden for the environment

Propspeed does not contain copper or zinc compounds, nor other poisonous components. In general, other foul release systems are based on delayed emission of biocide substances. Rapidly rotating parts emit biocide components faster, which leads to an (additional) environmental burden and a relatively short-lived impact of the foul release system. Propspeed works because it’s slick, not because it releases toxic components, and does not have environmental effects.



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