The first person to invent something which keeps a boat’s bottom clear of weed and barnacles but which does not cause whelks to change sex; mussels to suffer lock-jaw or winkles to self-eject, will become a multi-billionaire overnight.

Over the years I have tried nearly everything that has come out of a tin. Some coverings work better than others , but only the outlawed TBT was truly effective. Then Ecosea came along with their new product Cuprotect which they launched at the Southampton Boat Show in 2004. Their experts applied the stuff to my Contessa 32, Minstrel Boy, the previous month: August 2004.

The three coat system is unlike some copper anti-fouling systems in that the copper is on the surface, not in the body of the resin. That’s why no annual sanding down is needed to bring the copper up to the surface. It costs £100 per square metre. It is a great idea but in my case it has had disappointing results. It is guaranteed for five years.

The last time I wrote about Cuprotect was in the February 2007 YM when I described how the hull was heavily fouled on both sides of the keel after a season on a swinging mooring at Grays, Thurrock on the River Thames. An expert from Ecosea inspected the hull and said that the slime had encouraged barnacle growth. In March this year an Ecosea technician arrived at the boatyard and put a small patch of Cuprotect on the starboard side where he thought it had worn thin. He also coated the hull with an acid to ‘liven it up.’

This year I have had the boat moored at Paglesham on the River Roach in Essex. Here there is less mud in suspension than in the fast flowing Thames. But the results are patchy.

I launched on 23 May this year and I dried the boat out on 3 August. That is just 73 days afloat. Her hull was badly fouled on the starboard side with barnacles supporting a three inch growth of ‘beard’, but clearer on the port side. You can see the results above. Her starboard side would be facing the sun on the flood which may run for longer than the ebb at Paglesham and may explain the difference. Either way the search for the Holy Grail of anti-fouling continues.