Natural Pool for the UK - maintenance and water temperature

Hi David,

It is great to come across other self-build adventurers from the UK.

I have a couple of quick questions for you:

1) How much maintenance do your ponds need in order to maintain the water quality and keep the ecology of the pond healthy? In particular I have a garden pond which suffers from duckweed - is this a problem with your natural pools?

2) I wonder whether the temperature of the water reaches a level that could be comfortable for swimming in the UK, bearing in mind the recent poor summers that we have had here in the UK. How often are you able to use your pools?

Thanks for opening up a whole new area of possibilities for me.

Graham

Idk duckweed seems like a nice endless supply of mulch and fodder for me.

Hi Graham,
the only maintenance is pulling out some organic matter in the autumn, usually just dragging some decaying vegetation out with a rake. This removal of organic matter will compensate for the nutrients the pool has collected throughout the year.
The key is to construct the pool so as to minimise the nutrients entering the pool, (for example constructing the edges to prevent surface run-off water entering the pool).
The higher plants (lilies etc.) in the pool will compete for what nutrients are left in the water and deprive algae and duckweeds.

I did some simple heat calculations based on our intermittent summer weather and came to the conclusion that insulating the lower part of the pool was beneficial to keeping the temperature "swimmable" - especially for smaller pools. I usually swim in the pool most days. I have even built a sauna to bring the pool alive in the winter!

This is me breaking the ice and surviving my first winter swim.

David, in your last post you mentioned you would recommend insulating the lower portion of the pool wall to help maintain heat. what would you use or have used to insulate? Is it in contact with water or is it dry? Thanks.