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Bonda G4 Black Pond Sealer (5kg)

Manufacturer: Bonda
bonda g4 black pond sealer (5kg)
RRP: £186.49
This product is currently out of stock

Product Description

Used to paint concrete, seal it and makes it waterproof.

Concrete-based ponds need a final render sealing to stop the water getting in and lime leaking out. G4 has been long-established as the market leader for this task.

When using the black paint, the first two coats must be G4 Clear. This is because the G4 Clear provides the maximum non-porous seal and adhesion. A further two coats of G4 Black can now be added, making a total of 410g per square metre clear and 400g sqm black.

The amount of G4 you will need depends on the internal dimensions of your pond. For example let's say the pond is 3m x 2m and 1m deep.
1) Work out the area of the bottom by multiplying the width and depth in metres (in our example 3 x 2m = 6sqm).
2) Find the area of one of the sides (depth multiplied by width or length) then multiply by 2 to cover both sides (in example sides 1 = 2 x 1 = 2sqm x 2 = 4sqm).
3) Find the area of the other pair of sides: (in example sides 2 = 3 x 1 = 3sqm x 2 = 6sqm).
4) Add up sides and floor (6sqm + 4sqm + 6sqm = 16sqm).
5) Multiply total by 550gsm = 16 x 0.55kg = 8.8kg.


  • G4 can also be used to coat flagstones, waterfalls, statues and other concrete products to make them safe for your pond

  • There is enough sealant in a 5kg tin for 9sqm

  • Leave for 45-60 minutes after first coat

  • Do not leave for more than 4 hours between coats

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