The best pond sealant, beware of imitators!
Concrete-based ponds need the final render sealing to stop the water getting in and lime leaking out. 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 (in our example 3 x 2m = 6sqm). 2) Find the area of one of the sides. 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.