Tufa in ponds

Credit: Brand X Pictures/Gardening/Sandra Ivany

The organic component (peat or coco) of tufa will, over a period of time, degrade and break down. If you are interested in using this type of container, consider leaving out the organic component and making it from concrete only, but you still need to pay attention to the pH in your water and the plants that grow in the containers.

Lime is a primary constituent in cement and, when present in large enough quantities, can negatively affect water pH levels. This is particularly important if you have fish. The cured pot can be leached to reduce the problem. Be diligent with water pH testing and ensure your water is stable before adding plants or fish.