Guppies in a pond

My experiment with keeping guppies in a small pond was successful! It's only a 250 litres pond (made of a ready-made form), and of aquatic plants, the arrowhead did best. Watercress died. Later on I added a thick willow branch, which developed roots and shoots in and around the pond; it was mostly for lizards which kept drowning in the water... they stopped after I added the willow.
I also threw in some excess pistia and duckweed from my aquariums, but they didn't grow much in the pond; just survived.

Speaking of guppies - I had a small group of them from my aquarium, and a bigger group from someone else, which I exchanged for my fish and plants. I released them all into the pond and I thought that they will get eaten by predators, jump out or get hurt by extreme conditions... nothing like that! Guppies are really hardy. They survived heatwaves (water was still colder at the bottom), and after worst nights (only +12 degrees Celsius at night, or a storm) I found newborn fry in the morning, and the babies usually survived.

So they reproduced a lot, and now (autumn is coming) I will keep a group of fry in the aquarium, to release them again next spring. The only filtration was provided by a small solar pump; I only cleaned the sponge (really tiny) every now and then and it worked really well. Of course I also removed excess algae (to use them as mulch around the pond), and sometimes I used the water for plants (and replaced it with rainwater from a barrel), but in general the pond didn't need much maintenance.

There is a layer of soil on the bottom (just regular soil from anywhere in my garden seems to work well enough). Once friends visited with their kids and they were very disappointed that I didn't allow their kids to jump into the pond and play... oh well, the tiny ecosystem is too fragile for that! I was worried that larger birds or other animals will mess it up too, but they didn't. I guess it would be more child-friendly if it was larger.

This is a fantastic project, thank you for sharing your success!

Please post back as seasons change. I think your pond will morph as seasons change, wildlife visits, and plant life adapts.

Your little ecosystem inspires me, Flora!

Thanks! I'm planning to remove most of the water and the guppies, so it won't be very alive in winter... ideally, guppies need at least +15 during the night (they say +20, but mine survived +12...).

Also, I forgot to add that there is a thick layer of sheep wool under the pond, mostly to protect the form from any sharp rocks etc, but also to stabilize it and the temperature, and as a fertilizer for plants around. So maybe I'll take everything out to see how the wool decomposed, and I'll add more wool in spring? We'll see.