This product is now regulated by the HSE and we can only sell and send to business users. If you are not a business user we will need to refund the item from your order. Please include your business name at checkout.
Please complete the required details using the following form:Complete the Oxalic Acid Form.
CFS Oxalic Acid Boat Cleaner & Rust Remover is a concentrated cleaning product that tackles rust marks, yellowing, waterline stains and other stubborn discolouration on boats. Supplied as oxalic acid crystals, it can be mixed with water to create an effective cleaning solution for gelcoat, fibreglass, stainless steel and timber surfaces.
Ideal for boat maintenance and restoration, the cleaner works to break down difficult staining while reducing the need for heavy scrubbing. When diluted and applied as directed, it can help restore tired or discoloured surfaces to a cleaner, brighter appearance, making it particularly useful when preparing a boat for the new season.
The concentration can be adjusted to suit different cleaning tasks by mixing one part oxalic acid with approximately six to ten parts water. This versatile mixing ratio provides a stronger solution for stubborn marks or a more diluted cleaner for lighter staining, while the concentrated format offers excellent coverage and long-lasting value.
Application Guidance:
Mix one part oxalic acid with approximately six to ten parts water, selecting the dilution according to the severity of the staining. A small amount of washing-up liquid can be added to help the mixed solution remain on vertical surfaces during application.
Oxalic acid is hazardous and must be handled with care. Wear suitable protective gloves and eye protection and work in a well-ventilated area.
Code: 11914
Customer Reviews5.05 5.0/5 Based on 44 reviewsShow all reviews
Good priceReviewed by Pjm on 27 Jul 2026
Prompt delivery
Oxalic AcidReviewed by William.bayne on 14 Jul 2026
this is a great cleaner. however there are no advice on best use. ie if you make the solution up and then add some wall paper paste ind car shampoo this helps the product to stay on the hull longer and is more effective.
excellent productReviewed by Paul on 28 Jun 2026
excellent product
Works well hoodReviewed by Siamey1977 on 15 Jun 2026
Perfect great product
excellent product. 0.5Kg Oxalic Acid crystals.Reviewed by Nigelcki on 13 Mar 2026
I bought half a kilo of oxalic acid crystals, the intention of removing a heavy rust stain from the shot locker box on my boat. ( A shot is used to mark a wreck for the divers on board.) They are cast iron and they rust in the salty sea, and have been in the box for over twenty years. I applied the product as per the instructions and left it overnight and came back to find a pristine clean shotbox. See the accompanying photos. I'm well pleased with the result; and i'm going to clean the fish locker and the bilges next.
Fibreglass Supplies use Royal Mail, APC Overnight and the National Hazardous Pallet Network for our Next Day Delivery Services.
Royal Mail
Orders of up to 2kg will usually be sent using a Royal Mail First Class Service for National Next Day Delivery.
APC Overnight
Orders over 2kg and up to 30kg will be sent using a Fully Tracked Next Day Service using APC Overnight. Some smaller Roofing Kits that weigh up to 30kg in Total would be sent on this service. This includes Resins, Gelcoats and Topcoats which are classed as Hazardous and are decanted into 5kg Tins or Pales to comply with the Transportation of Hazardous Goods Act.
Pallet Network
All our larger orders by weight would usually be sent using the National Pallet Network. Non Hazardous Items can be sent using either the Pallet Network or APC Overnight.
All Hazardous goods over 30kg (which includes Roofing Kits over 30kg in total weight) are usually sent using the National Pallet Network on a Fully Trackable Next Day Delivery Service.
Click & Collect
All orders are eligible for Click & Collect. Pick up your items conveniently from our Cattedown Store, available Monday to Friday between 7:30 am and 4:30 pm (excluding Bank Holidays).
NB - Please note that our Direct Control of the Delivery Element extends to making sure we pick pack and dispatch all orders on time. As we have no Direct Control over the performance of any individual courier we would not be responsible for refunds due to the late arrival of any order.
We always work hard with customers to overcome any issues that arise so please call us if you do have any concerns with regard to tight delivery deadlines so that we can provide great advice if needed.
Please read our Returns policy laid out below.
Under the Consumer Contracts Regulations 2014 you are entitled to return goods within 14 days of delivery for a refund of the cost of the goods. The delivery costs and any packaging are not included in the refund. The returned goods should be in the original containers and unopened. It is the customers responsibility to pay for the cost of returning goods to our Business Premises.
Some of our products are made to order and as such once ordered are non refundable and non returnable. These include coloured gelcoats, topcoats and resins.
These Consumer Regulations do not apply to business purchases (B2B). However we will always help in any way and look to find a suitable and mutually acceptable solution should any issues arise through the order process.
It is the customers responsibility to understand the suitability of the product before its use. Technical and Safety Data Sheets are available for all products where applicable. These can be found on most product description pages or if not are available on request. If you are unsure please do not hesitate to contact us for expert advice and product suitability and application.
To organise a return please contact us on the following.
