How to Install a Preformed Pond
Step-by-Step Garden Pond Guide
Installing a preformed pond is a practical way to create a garden pond without cutting and shaping pond liner. The key to a successful installation is careful marking, accurate levelling, and properly supporting the pond shell during backfilling.
This guide shows the basic installation process for a rigid preformed pond. The exact method may vary slightly depending on the pond model, ground conditions, and the manufacturer’s own instructions.
Tools and materials you will need
- Preformed pond
- Spade and shovel
- Soft sand or filler sand
- Spirit level
- Long straight edge or timber batten
- Measuring stick or yardstick
- Garden hose and water supply
- Gravel, stones, soil, or planting materials for finishing the edge
Easy Step-by-Step Preformed Pond Installation Guide
1. Choose the location
Choose a suitable position away from deciduous trees and conifers where possible. Ideally, the pond should receive around 4 to 6 hours of sunlight per day.
2. Gather your tools
Before you start, make sure you have a spade, shovel, filler sand, spirit level, measuring stick, and a garden hose connected to water.
3. Mark the outline
Place the preformed pond in its final position and mark around the outside edge using sand, spray marker, or a similar visible guide.
4. Mark the depth zones
Mark the different depth zones of the pond separately. This helps you dig each shelf and deeper area to the correct depth.
5. Excavate the hole
Dig out the pond area, working gradually through the different shelf and depth levels. Allow enough space around the pond for adjustment and backfilling.
6. Test the fit
Lower the preformed pond into the excavation and check how it sits. Remove or add material as needed so the pond is not rocking or sitting unevenly.
7. Add filler sand
Use filler sand to correct uneven areas and support the base and shelves. The pond shell should be evenly supported, with no hollow gaps underneath.
8. Level the pond
Check the pond carefully from front to back and side to side using a spirit level and straight edge. Accurate levelling is essential before filling.
9. Backfill in stages
Fill the pond with around 150mm of water, then backfill around the outside to the same level using wet sand. Make sure the sand fills all cavities. Repeat this process in stages until the pond is fully supported.
10. Fill and finish
Once the pond is fully supported and level, continue filling with water. Shape the surrounding area with sand, soil, gravel, stone, or other finishing materials.
11. Decorate the edge
You can now plant and decorate around the pond. Fill the perimeter and planting areas with suitable gravel, stones, or planting media as required.
That’s it!
Your preformed pond is now installed and ready for planting, decoration, and adding suitable pond equipment if required.
Important installation tips
- Take your time with levelling. A pond that is even slightly out of level will be noticeable once filled.
- Backfill gradually as the pond fills with water. This helps balance the pressure inside and outside the pond shell.
- Use wet sand around the sides so it flows into gaps and supports the shape properly.
- Do not leave unsupported voids beneath shelves, corners, or moulded areas.
- Check the manufacturer’s instructions before installation, especially for larger preformed ponds.
These installation images and instructions are kindly provided by Oase.
Click here to download the Oase preformed pond installation PDF