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I want to build a raised bond out of lightweight blocks (left over from another build). The pond will be 1.8m x 1.0m and only x2 blocks high. Is this advisable? Will it hold? We will incorporate a waterfall which will overflow in to a small wildlife pond on ground level. Any help please, thanks



On the ground no I dont think it will, its very shallow, 2 blocks deep - whats that 8-10" max? I think the whole thing would freeze and expand to shift the light weight blocks out of line thus splitting any sheet liner? You will not be able to keep fish either at this depth they need at least 2.5 to 3ft to over winter.

4 Sep, 2012


Please don't do it. I built a koi pond with 18 x 9 x 9" hollow concrete blocks. I built it 4 blocks high (3 feet) and didn't bother using reinforcing steel rods or fill in the holes with concrete.

2 weeks later, the walls blew out due to the pressure and i had to completely re do it....properly.

You will be amaized at the amount of pressure there...even at your proposed height (18" ?)

4 Sep, 2012


thanks, thats exactly what i needed to hear else i would have gone ahead and done it anyway. back to the drawing board then!

4 Sep, 2012

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