" At first you can buy a treatment to get rid of the ammonia. Water changes
help
too.
In the long run the pond needs to take care of the ammonia itself.
Normal fish waste produces ammonia.
(Spawning activity causes ammonia spikes and increased population but this
is
seasonal.)
Plants will use the ammonia up and/or a bio-filter will convert it.
I filter my pond through plants only. I keep the fish population very low
(the
frogs spawn in their own fishless pond - they're chorus frogs (USA) and
they
tend to avoid ponds with fish) - you can remove the majority of frog spawn
if
it overwhelms your pond and transfer it to a natural waterway.
I plant watercress in the waterfall stream to help filter my pond.
You can add more plants to your pond, if needed, and thin the population
down.
Also, if possible, keep the fountain on 24/7.


Thanks Kathy, I'll change the water ASAP. Is it worth chucking some "
treatment " in the new water or should I wait and see?