The Pond Nitrogen Cycle

The secret to ponds that function well and maintainthemselves lies in developing a healthy, balanced ecosystem that virtuallytakes care of itself. In order to achieve a carefree, self-maintaining ecosystem,an understanding of the nitrogen cycle is essential.

If you have a pond with fish in it, you're probably awareof all kinds of products that keep your pond clean and your fish happilyswimming. But what you're probably not aware of is the natural nitrogen cyclethat your pond uses in order to maintain a proper life balance. Ponds can beeasy to maintain by just understanding a few things about the life teeming inand around it.

The cycle starts with the fish eating the food we feedthem and then creating waste. The fish waste and other decomposing materialcreates ammonia, which in small amounts is highly toxic to the fish. Bacteriacalled nitrosomonas then oxidize ammonia into nitrite. Because nitrite is alsotoxic to fish, another bacteria called nitrobacter convert it to nitrate, whichfor the most part is not toxic to fish. Aquatic plants, including algae, takenourishment from the nitrate, reducing the nitrate level in the water,rendering the water fish-safe.

The process is ongoing. Ponds and other aquaticenvironments naturally use this process to gain the nitrogen they need in orderto live and grow. Plants use the nitrates to grow, producing oxygen as a byproductwhich is beneficial to the fish.

To help the process, follow these steps:
1. Have stonesand gravel in your pond. Bacteria that change the ammonia in waste into nitriteand nitrate live on the gravel and other surfaces in the pond. Give them a nicehome and they'll do their part in keeping it clean.
2. Have a goodfiltration system and highly oxygenated water in your pond. Use a settling tankso that large waste won't clog the filter.
3. Don'toverpopulate your pond. A lot of fish create a lot of waste and your filterwon't be able to handle it, and the pond will have too many toxins for life toabound.
4. Clean yourfilter material using water from the pond (tap water will harm the beneficialbacteria). Test your water for ammonia and nitrite and watch for peakinglevels.
5. Remove anydead material from your pond. Leaves, twigs, that dead frog…it becomes too muchto decompose and these big materials create too many toxins for the goodbacteria to quickly take care of.

Following these steps will help you create thewell-maintained pond you want and keep your water quality up to par, promotingsuch clarity that will make your pond seem like a scene in a Kincaid painting.