Question
I just read the article on here about foaming ponds  how to you  do a part water change? the fish seem fine they are swimming quite happily but dont come up when the foam is there  i dont  have a filter yet could this be a cause ive tried the  liquid you can get to stop foam but that doesnt work at all, im concerned as i dont want the fish to end up dying in there.

Answer
Hello Cheryl!
Foam in ponds is generally caused by an overabundance of nutrients (fish waste). This can quickly turn into a dangerous situation for your fish -- they are basically swimming in their own sewage.
The water needs to be tested for nitrite and ammonia as soon as possible. Beneficial Bacteria can be used in high doses to help the situation immediately. All feeding of the pond fish needs to stop until the water is healthy again.
Generally a pond filter is needed to keep the pond fish healthy, unless there are many plants and just a few goldfish which do not get fed.
Koi always need a filter.
Brigitte
www.pondmarket.com