Tag Archives: oxygen

Aerated Ponds Look Pristine

Aeration simply means adding oxygen to the water by keeping it moving and free flowing through your pond’s circulatory system. This is vital for the health of our koi and also just a great way to keep your pond looking great.

 

Koi ponds and plants (including all forms of algae), organic life and of course the koi fish themselves consume oxygen. Koi are rather special in that they need a considerable supply of oxygen in the water for their survival and well-being. The more algae and bacteria that are in the water the less oxygen there is for fish.

 

There are lots of things in your pond that are competing with your fish for oxygen. Plant life consumes oxygen during the night and gives off carbon dioxide. This process is reversed during the day. The more organic stuff that is in the pond (fish, plants, decaying material) the higher the oxygen demand of the entire ecosystem. Decaying organic matter also uses oxygen as it is converted into waste and the ‘dirtier’ the pond. This means the more trees your pond is situated under, the higher the requirement for oxygen.  The warmer the weather is the less oxygen there is in your pond.

 

Waterfalls, and air pumps can supply oxygen. Waterfalls are extremely efficient when it comes to providing good aeration but many ponds just don’t have them. Many people turn these water features off at night, which during a summer night is just when the koi need to be aerated the most.

 

There are several ways to aerate your pond but the most common ways are to install a water pump with an airstone, a commercial aerator such as a bead stone pump or a waterfall.

 

Airstones are ceramic, synthetic or natural stones through which air is blown by an air pump. These stones are characterized by hundreds of tiny holes, which create bubbles in your pond system. This allows more oxygen to circulate through your pond’s ecosystem.

 

You can also buy Plexiglas tubes that sit on the bottom of the pond and funnel oxygenated bubbles up towards the ponds surface. These commercial aerators are offered in both battery operated and outlet operated versions.

 

An external pond filter or waterfall tank can be positioned against the shallow edge of the pool to create a waterfalls.  Just make sure that the waterflow flows to just a trickle as too much water hurts the koi.

Biological Filters That Can Keep Pond Fish Healthy

You don’t have to pour a bunch of chemicals into your koi pond to keep it free from bacteria. A biological filter is a medium of some kind that at converts harmful nitrogen by products from aquatic animals into less harmful nitrates. This type of bacterial occurs naturally in nature’s lakes and streams. It usually attaches itself to rocks or stones.

 

These bacteria are already noticeable on the walls of most koi ponds. They also can be found on the inside walls of the pond plumbing, attached to the skimmer basket, and on the rocks that form a waterfall. The reason we build biological filter systems is to increase the available surface area for these bacteria to colonize. It is simply not enough to dump a plastic liner into the ground and surround it with dirt. Rocks help grow the bacteria that eat nitrates that are harmful to koi.

 

In an effective koi filter, two, three or four chambers of suitable media, on which our nitrifying bacteria can grow and thrive, normally represent the biological stages. These chambers can be any shape. They should also be benched steeply towards a central drain valve in the base of the chamber, so that any solids that do collect in the chambers can be easily be removed by you.  If you own a biological pond filter it is important to unclog it to maintain superior water quality.

 

This green stuff that grows on biological filter mediums is called a biomasse. Bimoasses of friendly bacteria need both an adequate supply of ammonia oxygen and nitrite to survive. Again if the mechanical stages of your filter are not working effectively, the biological media will gradually become clogged with debris and your good bacteria will die.

 

In order to ensure the biomass has an adequate supply of oxygen, air should always be pumped into the filter, by placing air stones under the media, on the filter grids and air introduced by way of an air pump. Without an air pump, a biological filter will never perform biologically as it should.

 

There a wide range of medias to use in the biofilter. Gravel is the most popular choice but synthetic medias are also a good choice.

 

Synthetic medias don’t have a lot of the problems that gravel does. Being lightweight and less clogging makes synthetic medias easier to handle and clean. Most of the synthetics have a large surface area per cubic foot for growing bacteria. This attribute gives a bigger biofilter in a smaller space. However synthetic medias may not grow the “algae lysing” type of bacteria that naturalizes very easily in genuine pools and steams. The “algae lysing” bacteria grow better in slightly stagnant and low oxygen zones created by a rock, gravel or stone based filtration media.