Japanese Zeolite 20kg
It removes ammonia from your pond's water by trapping and absorbing it.
Since ammonia is the principal killer of pond fish, it's important to keep the ecosystem of your ponds healthy. Zeolite can help with this process.
As the ammonia is absorbed by the zeolite, an overnight soak in salt will free the ammonia that has been trapped, allowing the zeolite to be reused.
Zeolite must be removed from your filter system if you need to treat your pond with salt or other drugs, as doing so will cause the ammonia to be released back into the system.