Antifouling

[DaveS]

I was up at the boat on Friday, doing some 'bits & bobs' on the boat, when I got chatting with another boat owner, in the marina.

I happened to mention that my boat was coming out of the water for the winter, and that I was going to get the workshop to jet wash, and antifoul the hull, before putting the boat back in the water in the spring.

He said that it then wouldn't need re-antifouling again, for 3 to 4 years, as the water of broads allows antifouling to remain effective for much long than antifouling does in a salt water environment.

Possibly something to do with the alkalinity of the water of the broads?

Fact or fiction ?

Dave

[Guest]

Heard it said many times. I've always kept my boats anti-fouled so I can't comment but I've certainly never seen any growth on them. Loads of damn scale, but no marine growth. My boats are faster seagoing types though and dragging along any marine growth will have a greater impact and, whilst I've not done much activity at sea I always try to maintain the boat in a manner where it could do so without too many worries.

Might not hurt just to put a little around the waterline, or least check that that which is there is in good condition. Judging by the water quality on the broads (2 parts water, 1 part mud, 1 part Imperial Leather) I doubt sunlight penetrates far below the surface but those areas where it does are most likely to see growth - and that would be the cms around the waterline.

[Poppy]

Dave,

Whilst weed fouling may not be a great problem on The Broads, there is an invasive species, the Zebra mussel, which is causing increasing concern. They are relatively small, with adults ranging from 1/4 to 1 1/2 inches long, can grow in large colonies underwater and have the capacity to block inlets etc. Their removal can be a right pain! My boat has been affected, but luckily only moderately. They are known to infeast pretty well all of the Broads network.

http://www.broads-authority.gov.uk/mana ... ecies.html

[Antares_9]

Absolute nonsense Dave, there is no comparison between salt and fresh water antifouls anyway as they are targeted at different species of growth and neither will last 4 years, two years is about the best you can expect even in the best scenario. Problem is now that antifouls are a lot less toxic they are far less effective than they used to be because that’s how they work, by being toxic. So the less toxic the less effective and it is now quite common for boats moored in salt and brackish water to need a lift and scrub in mid season. One caveat is that if you moor your boat in a brackish area and use it a lot in the fresher areas or vice versa growth is restricted as fresh water organisms don’t like salt water and salt water organisms are not keen on fresh water,

[DaveS]

Thanks for the reponse guys, an interesting read.

As you say David, toxicity is the 'key' to the effectiveness of antifoul coatings, and of course TBT was very effective. In fact too effective, in that it was killing off shellfish etc.

I believe that copper is a 'key' ingedient, and that boats with copper clad hulls, don't foul up.

I think the point the guy was making, rightly or wrongly, was that for whatever reason, the antifouling remains effective longer in broads water. But then, its probably something that he had been told by someone else, and so on.............

Dave

[Antares_9]

Indeed Dave most antifouls are cuprous based now but contrary to popular belief copper clad hulls still suffer once an oxide layer forms rendering it less effective. One point to remember for those with outboards and sterndrives, make sure at least a one inch gap is left between cuprous based antifoul and the drive or outboard or you will accelerate corrosion of the alloys they are made from. Also never use a cuprous based product on an outboard or sterndrive for the same reason.

[senator]

Following on from David's post, those antifouling Stern Drive boats might want to look at Seajet emperor 034, It is a 2 year antifoul suitable for fresh, Brackish and salt, eroding but suitable for up to 40 knots and best of all you can paint everything in it, Hull, Outdrives the lot.

Not cheap but its performance on White Lady and Clanny has been superb.

Ian

[marshman]

Dave - I have to say that mine lasted 3 years last time with very little weed growth. Out at sea we were lucky to get 6mths on the N Kent coast and that was with TBT!!!

I agree zebra mussels are more of an issue and whilst i had a few last time, nothing that impeded 40hp or so!!!!!

It however is not just a question of antifouling however - it does plastic hulls good to come out of the water now and again and enables you to clean up the hull as well. It is expensive however and whilst I used to liftout every other year, there may well be a tendancy to do it every 3 in future!!!!!!

[DaveS]

Dave - I have to say that mine lasted 3 years last time with very little weed growth.

Well I'll be starting afresh in the spring, so lets hope mine lasts as long as yours did

The boat will be coming out of the water around mid November, and I guess will go back in March/April time.

Dave

[jimbo]

Hi Dave, I'm moored in Beccles and my boat was lifted out earlier this year, after 2 and a half years afloat. Very clean underneath with minor growth around the water line only.