Originally Posted by ponyboy
If you are putting koi in a pond
Rocks on the bottom are a no no they collect all the waste and will harm fish
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That statement has absolutely no basis in scientific fact. Rocks and gravel in the bottom of a pond promotes a wider growth and diversity of periphyton and micro-organisms. These two are not only the foundation for the aquatic food chain they provide the bulk of a natural diet preferred by herbivorous and omn- ivorous fish such as Cyprinus carpio/Koi and Carassius auratua auratus (Goldfish) and, in addition, perform the function of 'breaking down' and consuming any organics that may settle.
A pond with properly sized filtration and the correct flow rate will not accumulate sediment providing feeding is controlled regardless of stocking levels.