Posted on 10th April 2017 by Paul King
When I needed Insulating Koi Carp Pools – Considering Options, I faced a common problem: my heated pond lost heat fast. With a thermostat set at 15 °C (59 °F), steam rose every morning. I watched my money literally evaporate. So I urgently explored insulation ideas and considered what the cover must handle.
First, our rear garden is windy, so the solution must stay in place and not blow away. Secondly, it shouldn’t look ugly. Third, it must pack away for summer storage without needing extra space. Then, I needed easy fish feeding access. Lastly, it must prevent fish from stranding themselves by jumping onto it.
Pergola-style cover similar to David and Audrey’s solution
However, a pergola would shade our garden and our neighbors’.
Temporary frame and cover
But building a sturdy, secure frame over an irregular 6 × 4 m pond seemed impractical.
Polystyrene slab pool covers
Though insulating, fish jumped on them. Plus, PVC covering can leach chemicals.
Pool insulation balls from Euro-Matic
Used to cover reservoirs and discourage waterfowl.
Available in various sizes; we chose 50 mm.
They float and contour to every nook, including skimmers (so place carefully!).
They rarely blow away and cause no damage if they do.
Clear balls let in light, and you can layer them for extra insulation.
I tested them and saw immediate results. They formed pleasing patterns when the wind blew across the surface. Feeding stayed easy—I created a small feeding area using waste pipe frames.
When reviewing Insulating Koi Carp Pools – Considering Options, plastic balls stood out. Manufacturers claim they:
Reduce heating costs by up to 75%
Cut evaporation by about 90%
Block UV rays, thus slowing algae and weed growth
Lower ice formation by up to 10 °C (50 °F)
These benefits matched my needs: efficient, low-maintenance insulation that tackles heat loss and evaporation effectively.
Storing the balls is straightforward. I returned them to their cardboard box and plastic bag and stored them in the loft. They kept well all year. One small downside: algae can form on balls left underwater. To mitigate this, I plan to add salt during winter, which should help reduce algae buildup.
