Plants for Koi Pond - Pandan

The fragrant pandan plant (pandanus amaryllifolius) is commonly found in South East Asia and is a good plant to grow in your Koi pond. It can be grown in soil or in water (hydroponics), hence making it suitable for a Koi pond. The leaves give off a nice fragrance and is used widely in South East Asian cooking and baking as a flavouring. Examples are the pandan cakes and other sweet deserts, Hainanese chicken rice and Thai pandan chicken (leaves are used to wrap the chicken meat and fry together).

The pandan plant grows easily in my Koi pond, absorbing the nitrates from the water. The leaves are regularly harvested and given away to friends and relatives. They have told me that the leaves from my pond are much more fragrant than those they bought from the local markets or supermarkets, which I believe are grown in soil.

Another use of its leaves would be as a…. cockroach repellent! Some taxicab drivers in Singapore like to place a bundle of pandan leaves in their taxicab to get rid of roaches and also to provide a nice aroma in the cab. Next time you bought a taxi in Singapore, look out for the bundle of pandan leaves at the back of the cab and ask the driver about it.

Regular Koi Pond Maintenance Tasks

Koi pond maintenance can be broken down into the following tasks.

• Partial Water Changes
• Filter Maintenance
• Pond Maintenance
• Replacing of failed parts

Partial Water Changes

Do not change all the pond water at once. Do regular partial water changes. Partial water changes are essentially to remove accumulated nitrates from you pond water. Nitrate is an output from the biological filtration system and although not harmful to the fish, a build-up of nitrates in the pond can lead to algae bloom, water discoloration (brownish tint) and in the long term harmful to the pond occupants (except for the plants!).

Filter Maintenance

Biological filtration relies on bacteria to work, so it is best to clean the filter only when needed. Filter media like filter mats, coral chips, beads, would clog after long periods of use and start to restrict the flow of water through them. When this happens, the media would need some cleaning. Depending on your filter design or filter system, back-flushing of the filter media (reverse direction of water flow through the filter) is a good way to remove accumulated dirt within the filter media. Never clean all the material or filter chambers at the same time since you need to have some bacteria for the filter to work. You may want to reduce the fish feeding for about a week after filter maintenance to allow the biological filter to re-stabilise itself. Stop the feeding completely if you observe that the Koi is listless, lying at the bottom or show other signs of distress.

Pond Maintenance

Over time debris from fallen leaves, sticks, fish waste and sludge will build up at the bottom of the pond if you do not bottom drains build into your pond design. Ponds with bottom drains will typically not suffer a built-up of such debris since the dirt is constantly being suck into the filter system. Hence pond maintenance is relatively easy or not really needed. For ponds without bottom drain system, a pond vacuum cleaner would be needed. Just like household vacuum cleaners, pond vacuum cleaners suck up the dirt from the pond where it can be disposed of, or used as fertiliser.

Algae removal may be needed, if you did not do regular partial water change or did not have a good filter system. In this case, we are referring to string algae. Algae that grow on the side of the pond are alright and the Koi loves to graze on them. Best way to remove string algae is to twirl them round a long stick, like cotton candy.

Replacing of failed parts

Pumps and electrical parts including bulbs for UV system and underwater lights do not last forever. Typically lifespan of my submersible pump which runs non-stop is about 2 to 2.5 years. When designing your pond and piping system, make sure such maintenance can be carried out easily without having to drain your pond! Have a spare pump on standby as Koi dies after a few hours without aeration.

For more information on pond maintenance equipment such as pond vacuum cleaners, check out these online stores (PondKeeper UK).

Koi pond at Singapore Changi Airport

Talk about being koi crazy! I can’t help looking and appreciating Koi ponds where-ever and when-ever I encounter one, whether in public places or in someone’s home. The first picture I took on my recent vacation to Bali is not the spectacular sunset or beautiful beaches of Bali. Instead it was the Koi pond at the Singapore Changi Airport.

The pond is located in the Transit Hall, Terminal 2. It is a relatively large pond with a good layout, natural setting and surrounded by very nice plants like ferns, orchids, palm trees and other ground coverings. A bridge spans across it for transit passengers to sit, relax and view the Koi. It is a good photo stop where the above picture is taken.

Pond depth seems to be shallower than a typical Koi pond since the pond is built on top of the floor slab and the pond builder cannot do any digging. I doubt you can raise large Koi in it.But then, this is not a hobbyist’s pond. The fish are probably raised to its large size elsewhere and transferred to this ornamental pond for showing only. The water is clear, and the filter is well hidden. I wonder how they maintain this pond, e.g. change the water, clean the filter. This is especially with the airport operating almost 24x7 non-stop and having a constant flow of passenger traffic.

Overall, this pond is a “must-see” for Koi or pond hobbyists who comes to Singapore. Good place to relax till you board your plane.

And yes, I did finally took some pictures of the spectacular sunset and beautiful beaches in Bali. Enjoy.

Koi Pond or a Water Garden, Why Not Have Both?

Most Koi keepers will tell you that Koi and water plants do not go well together. There is some truth in it as Koi eats plants. Some serious Koi lovers will not include any plants in their Koi pond. They would keep their pond layout simple. Their main or only focus is on their expensive, show-grade Koi and they would not want sunken plant pots that the Koi may bump into or fertilisers and rotting plant waste that may contaminate the pond water. Although water plants do help remove nitrates, increase oxygenation and provide shade, the serious Koi lovers’ ponds will have other means to take care of these.

However, most pond keepers, including myself, would like to have some greenery in their Koi ponds so as to have a pond that looks natural and able to blend with the overall garden. The best compromise is to include a separate water garden that contains other fishes and aquatic plants, that is physically separated from the main Koi pond that contains only Koi, but sharing the same filtration system to reduce cost. It is important to decide this as you design your pond and plan the layout. A water garden is usually shallower than the Koi pond which is ideally more than 4 feet (1.2 meters) in depth. Another solution is to include a narrow and shallow shelf (of about 1 to 2 feet deep) at the edge of the Koi pond where water plants may be grown. In any case, the selection of suitable plants for your Koi pond is important as Koi eats plants.

Water plants can be broadly classified into 4 categories:

• Marginals or Bog pond plants that naturally grow on the edge of a pond or are slightly submerged. These are the best plants to include in a Koi pond if your aims are to beautify the pond, blend the pond with the overall garden and have ease of maintenance and growing. I plant these in pots and place them, half submerged, in the shallower part of the pond. The aim is to keep the soil and roots moist but with the main parts of the plants above the water surface.
• Submerged plants or Oxygenators that provide a pond (or fish tank) with oxygen through the natural process of photosynthesis. These plants would be nice in an aquarium or fish tank but not recommended for a Koi pond.  They will not survive in a Koi pond. Koi eats plants!
• Floating plants or Floaters that floats on the water surface. They multiply rapidly and help to keep algae and water temperatures down. However, they are not suitable for a pond with Koi. Koi tends to eats the roots and shred the leaves. In fact, they love the roots more than the leaves. So, floaters are best grown in a water garden that contains only small fishes.
• Water lilies and lotus that grow submerged under water but with floating leaves and/or leaves that grows above the water. Water lilies need regular fertilisations to keep them blooming daily, so growing them a pot that can be easily accessible is best. The pots are placed in water of about 24 inches depth. They are best kept in still water, away from any venturi pipes or waterfall that will cause ripples or disturbance at the water surface. Large Koi tends to dig at the soil around the plants. A top layer of pebbles or stones large enough to cover and protect the soil is needed in the pot. They are best grown in a water garden that contains only small Koi/fishes or in a water garden that is separated from the main Koi pond containing large Koi.

In summary, if you want both Koi and plants in the same pond, stick to marginals or bogs plants. If you want to include water lilies and lotus, find some means to protect them.