Manure from chickens, goats, sheep, ducks, pigs, rabbits, cattle and horses are excellent fertilizers for fish ponds. Other examples of organic fertilizers suitable for ponds are digested sludge from biogas generators, molasses from sugar cane factories, composted vegetation, table scraps and waste water from animal slaughter houses. Examples of materials that are NOT good organic fertilizers are rice hulls, sugar cane stalks, sawdust or other materials that require a long time to decay.
Animal manures make good fish pond fertilizers.
Organic fertilizers decompose and release nitrogen, phosphorous and potassium which are used by phytoplankton for growth and reproduction. In this way more natural food organisms are produced for fish to eat. These organisms provide nourishment for fish even though in some cases the manure itself may have no direct food value when eaten. This is in addition to their effect as fertilizers and attachment sites for fish food organisms as described above. The result is enhanced fish production.