DIY Guides » Koi Pond

Stopping Koi Pond Algae

Mike — Sun, 19 Sep 2010 17:02:52 +0000

Stop Koi Pond Algae

The growth of algae in your Koi pond is definitely not a good sight to be seen and moreover, it also provides a bad odor to the surrounding environment. If algae are not removed from the pond, it will somehow produce ammonia and if your Koi pond has excessive ammonia, it will reduce the oxygen supply thus threatening the lives of your fishes.

What you need:

To restrict the amount of direct sunlight
Add plenty of plants in the pond
Use UV filters
Installing proper filtration
Use supplement products to fight algae

Method:

The Koi pond needs to be placed in an area with partial sunlight because algae need sunshine for its growth. Placing the Koi pond in a partially shaded area will provide you with healthy water plants plus also limiting the amount of sunlight that can help the algae to feed on.
You can add plenty of plants in the pond to enable the usage of nutrients in the pond water and releasing oxygen. By doing this, the plants also help to cover the surface of the Koi pond and blocking sunlight from coming through and also preventing the growth of algae.
If you have the budget, you can also use the UV filter for your Koi pond. It may be expensive but it is a great solution in preventing algae growth. The UV filter works whenever the pond\’s water flows through a channel and is exposed to the UV light, it will kill off the algae before the water returns back to the pond.
You will need to install UV sterilisers if you have green water. You should however remember that you should not rely solely on the UV unit to get rid of algae in the water. The filter that you\’ve installed should be sufficient to solve the green water problem.
The filtration system that you installed should move approximately half of the pond\’s water every hour. Although the Koi fishes are not fond of strong currents, making half of the water in your pond per hour should be sufficient enough to filter the water. Using biological filters help prevent algae growth and also maintain environmental balance properly.
Supplement fish-friendly products can also be used in fighting algae for example; some of the products in the market will kill the algae automatically when they are used and also clean all the murky water inside the pond. There are also supplements that can only tint the pond\’s water into deep blue in order to limit the amount of sunlight from penetrating into the water thus preventing algae\’s growth.
You can also depend on the Koi fish to help you prevent algae\’s growth because Koi fish eats algae and other plants as a natural part of their diet. If you reduce the amount of food given, the Koi fish will definitely clean the bottom and also the sides of your pond.

By now, you must have successfully stopped and ended your Koi Pond algae.

Image Credit:

Flickr

Additional Reading:

The Guide to Owning Koi

Raising Healthy Koi Secrets

Stopping Koi Pond Algae is a post from: DIY Guides

Koi Pond – Ultra Violet Sterilizers

Tom — Sun, 07 Jun 2009 17:09:41 +0000

You will need to install UV sterilisers if you have green water. You should however remember that you should not rely solely on the UV unit to get rid of algae in the water. The filter that you’ve installed should be sufficient to solve the green water problem.

UV Steriliser is recommended for Koi keeping. Not only clears green water, it also sterilizes the water itself, killing harmful Bacteria that lives in the water. UV-Sterilizers kill 99% of floating algae as well as other living organisms. The do not however harm the beneficial bacteria that grow in filters and on rocks. They kill the organisms that are floating in the pond water.

How does it work?

Chlorella vulgaris, which is a single-celled green algae, require light and nutrients to survive. This algae is a sign that your pond is generally healthy, and even provide good food additive for farm animals. However, it does impede on your viewing of your koi.

The UV disrupts the internal structure of the algae, which makes them clump together to form flocculates, which can then be trapped and broken down by the filter.

When to use a UV:

You can keep the UV unit on all year round. However if you have a small pond you may find it useful in spring. You must protect your UV unit from frost if you live in a seasonal climate, especially if you run it all year round. Replace the UV lamps annually for peak performance.

How much UV do I need for my pond?

8-10 watts per 1000 gallons is usually recommended for green water eradication.

30 watts for a reduction of bacterial levels.

Take into account factors like flow rates and stocking levels.

Koi Pond – Ultra Violet Sterilizers is a post from: DIY Guides

Koi Pond – Venturi

Tom — Sun, 07 Jun 2009 17:08:52 +0000

Venturis are an effective way of getting oxygen into the water. While you can build one yourself, there are many choices that you can buy now at suppliers at reasonable price. A venturi works by compressing the flow of water, then releases it abruptly into a larger chamber which creates a vacuum. Air is introduced at the point of release, getting sucked into the stream of water creating the bubble effect at the end of the pipe.

Why aerate?

Aeration maintains a good dissolved oxygen levels in the water as reduces algae growth as it drives nutrients, nitrogen, ammonia, and soluble phosphates – all which are food for algae – to the surface air and out of the pond.

Aeration also increases aerobic bacteria that feed on nutrients on which algae and weeds need to grow, thus limiting the proliferation of algae when food supply is low. Aerobic bacteria will also eat organic sediment at the bottom of the pond. Over the winter months, aeration de-ices a winter pond because moving water won\’t freeze.

It is at this point of release that you will have to take special care when constructing your own venturi. The nozzle should reduce the inside diameter of the pipe by 50%. Fit the T-junction near the waterline, because the deeper it is, the more pressure needed and less air will be sucked in.

Test your construction before you glue the bits together. You don’t even need to glue anything else other than the nozzle so that you can make adjustments and maintenance/cleaning, unless of course if you’re setting the venture outside the pond (not submerging it) then you will need to glue everything together.

Cut, sand, and shape the PVC parts as according to the image above.

You can add a muffler for the venturi as they can get quite noisy if you use smaller diameter tubing. You can do this by drilling a few holes through a spice jar lid (one for the air pipe to the venturi, and several smaller holes for the air to enter the jar, then stuff the jar with some filter material. Spray paint the whole thing to camouflage it.

Use PVC plastic that is rated for potable water. Do not use brass natural gas fitting or any copper tubing as the nozzle because this will expose unwanted chemicals into the pond system.

Koi Pond – Venturi is a post from: DIY Guides

Koi Pond – Drains box

Tom — Sun, 07 Jun 2009 17:08:14 +0000

A drain box is where the bottom drains from the filters, vortex chamber, and filter overflow system are led. If you want to install any additional features to the pond, like a sand filter then it is recommended that you run spare 2″ pipe and blanking it off so that it is available later if required.

You will also need a 4 inch drain from the base of the drains box that is connected directly to the main house drains. Make sure that there are water traps on the pipe and that the set up meets local building regulations.

Fit slide valves over the stand pipes instead of rubber ‘O’ rings as they are more durable.

Constructing a drains box

Prepare the hole for your filter housing base

Dig a hole for the drain box within this filter housing base

Pour concrete into the bottom of the drain box hole to form the base of drains box.

Build a wall with 18 x 9 x 4 inch concrete blocks, arranging the blocks so that the height is level with the filter room concrete base.

Complete the filter housing base. Lay reinforcing bars, spacers, pour concrete and level as such.

Then start building the walls of your filter system. Render them as required or apply fiberglass if you so choose to do so.

You can add a steel grid over the opening of the drain box so that you can walk over it as well as check the pump and water level.

Koi Pond – Drains box is a post from: DIY Guides

Koi Pond – Pumps & Systems

Tom — Sun, 07 Jun 2009 17:05:23 +0000

You should by now have considered which type of pump and system that you will want to use with your pond, once you’ve decided which type of pond and filter system you will be using.

Pump chamber

Pump chamber is where you will fit the pumps, UV, air blower, and any other electrical appliances that support the filtration system. Regardless of which type of system you use, fibreglass filter units, or your own concrete block filters, make sure that you have a larger space for this as you may decide to fit something extra such as a sand filter or heating system.

The pumps needs to be well below the water level so that they will be full of water when they are stopped as most of them are not self priming.

The base of the pump chamber is the same level as the base for the filters, unless you are using large round filters.

You will need a pump that will be able to pass all of the pond water through the filter in 2-3 hours. So with a 6,000 gallons capacity pond, you will require a pump with a capacity of 3000 gals/hour. This is the actual pumping rate, which depend on the length of pipe runs and the design of the pipework with the minimum of sharp bends.

You will also need to take into account contact time – which is the time it takes frot he water to enter the filter till the time it exits the filter. Ideally this should be around ten to fifteen minutes.

Pumps

The pump the most important features in the system. It is important that you know which one you’re going to purchase. It is not just the cost and the pumping capacity that you have to consider but the running costs as well.

There are a few models that are available in the market. So you will need to do some research on which that would be best for your system. Look into pumps such as the Oase Aquamax which is available in various sizes and is available at 795 gals/hr for the 3500 model to 3300 gals/hr for the 15000 model. These are circulating pumps and are quite cost effective to run. There are also pumps like the Sequence if you want to pump a large amount of water with low electric consumption. While they are costly initially, they are effective and very reasonable to run.

These two pumps are used on big systems, you will need to use 2 inch diameter pipe with minimal number of bends in your setup.

Koi Pond – Pumps & Systems is a post from: DIY Guides

Koi Pond – Filter media

Tom — Sun, 07 Jun 2009 17:04:42 +0000

There is a wide range of filter medias to choose from for your filter system. The following are just some that are available in the market:

Brushes

Eficient at removing debris and blanket weed, brushes were very popular until a few years ago.

However they require regular cleaning and also a lot of maintenance, and is time consuming. They can also prove to be very difficult to clean around the steel spine.

Flocor

Flocor comes in two sizes, is lightweight and very effective. It is widely used of all the filtration media because it is easy to install, clean and maintain. The media has very good biological surface area per square inch than many other types of media.

They are usually placed in bags to facilitate easier removal and cleaning.

Alfagrog

Alfagrog is a volcanic rock and is still a favourite with many koi keepers.

This is also quite heavy and very rough to the hands so many koi keepers put it into net bags which are obtainable from most koi dealers.

Japanese matting

Japanese matting can be used for the full system, or in one or two bays with any other media. It requires heavy aeration, but the up side is that it needs very little cleaning.

Japanese Oyster Shells

Oyster Shells are used to maintain a balanced PH level in the ponds water. They are used to raise the PH level in water and are only recommended to be used in cases of lower PH levels.

They should be located in the last bay of the filtration cycle, and you will need to monitor the PH levels within the system

Crystal Bio Media

Crystal Bio Media is a eco-friendly glass media which is produce by heat of up to temperatures of 900 °C. This process creates a media with a surface-area up to ten times greater than most plastic alternatives. The media increases biological filtration, does not require much maintenance, and enhances nitrification. The Crystal Bio media can be used as a stand alone biological filter or as an addition to an existing filter system.

Kaldnes K1

Kaldnes media provides the maximum active surface area for the bacteria to colonise, more than other types of static media. It is this process which removes harmful ammonia and nitrite from the water.

The Kaldnes media works by moving within the filter and displaces old dead bacteria on the outside, making space for new younger heavier feeding bacteria to rapidly colonise. Within the wheel is a protected surface which enables colonies of bacteria to naturally follow their lifecycle, of maturing, dying and then fueling the latter stages of the nitrification cycle.

It is designed to provide habitat for both young and mature beneficial bacterial colonies. This process removes harmful ammonia and nitrite from the water.

Filter foam

Normally used in three layers and in smaller filter systems, therefore it is not suitable for the large filter units as they would require cleaning almost every day, and eventually they have to be replaced.

Bacta-Pur® LITHAQUA

Bacta-Pur® LITHAQUA is a marine mineral with a high content of minerals, trace elements and carbonates. It adjusts the mineral balance and improves the water quality and can be uses as a pond substrate for bacteria to grow on and for fish to play in, or use it as a filter medium.

It also neutralises acid pH and helps to restore carbonate alkalinity.

Bacteria House Media

The Bacteria house is a ceramic media that has been heat treated at 1300°c for 60hrs.

It is a porous media, allowing mechanical filtration where large organic solids and decaying matter are degraded at a far greater speed than conventional media.

Koi Pond – Filter media is a post from: DIY Guides

Koi Pond – Concrete block filter units

Tom — Sun, 07 Jun 2009 17:03:22 +0000

There is a toss up between purchasing a fibreglass filter units that come pre-built but are expensive, or to build your own concrete block filter unit. Get as many quote as you can from dealers and suppliers, then weigh out whether you want to buy a fibreglass unit or to build your own.

Sometimes it is better to build your own as you can then make the filter system fit into the space available in your garden.

Building a concrete block filter unit

1. Lay a 6 inch thick reinforced concrete base as you would like the base of the pond and for the glassfibre filter system.

2. You will need to include 2 inch diameter pipe work for the bottom drains.

3. Begin building up the filter walls with 18″ x 9″ x 4″ concrete blocks with about 4 inch thickness.

4. Position the vortex chamber. Remember that the concrete base of the filter must be level with the ground.

5. Build up the walls of the filter, allowing overflow from between the chambers.

6. Render the filters as you would like the pond. Hire a professional if you are not familiar with rendering the filters.

• Mix three parts sand to one part cement for the render coat.

• Apply first coat directly onto the block work. Complete the surface, then rough it up with a trowel to prepare the surface so that the second coat will adhere to the first.

The second coat is made up to the same mix as well as a waterproofing agent and Fibromix. Follow the instructions as per required by the manufacturer. Fibromix consists of glass fibres (so be careful when using this). It should be broken up and added to the mix. The Fibromix serves to give stronger surface, and minimises surface cracking.

• Apply this second coating mixture on top of the first. Allow to dry.

• Smooth the surface with a blow lamp with a yellow flame (or a cigarette lighter) by burning any fibres that stick out, then rub the surface smooth. You must ensure that you have a smooth finish.

• Use a pond sealer after to finish the surface. Follow the pond sealer manufacturer’s instructions carefully.

Method of application
• Apply the first coat of G4 with a brush, and allow the layer to dry to a finger-tacky point or dry enough to walk upon carefully. This would be approximately 45-60 minutes.

• Do the same with the second and third coating. Do not allow more thatn 4 hours between coats. G4 comes in Standard (brown translucent) and Mid Green – Black colour. So it you decide to use colour, apply 2 coats of standard and 2 coats of colour.

• Allow to cure for 72 hours. After that, wash down the pond with plenty of water, drained, and then be fill.

7. Round the corner if you choose to fiberglass the chambers, as you would the pond as well because the fiberglass will not adhere well to sharp corners.

Applying fibreglass

• Cut the fiberglass matting to length first, allowing for a one inch overlap on each mat.

• Mix the resin and the hardener with a ratio that depends on the ambient temperature where you live. Because the resin hardens after mixing, do not mix too much. Mix just enough for about 30 minutes work, before you proceed with another batch.

• Apply to the concrete wall with a lambswool roller and cover the entire space where the fibreglass matting will be hung. Make sure that there is a one inch overlap for the subsequent matting.

• Work your way around the pond, applying matting to walls and floor so that you don’t have to stand on drying resin.

• Once the whole of the pond is fibreglassed, leave it until the application becomes tacky before applying the flow coat. The flow coat is a gel which has had wax added at the time of manufacture and leaves a smooth glossy finish.

• Apply the flow coat with a lambswool roller. Leave to cure.

• Check the flow coat layer after 1 – 2 days and sand any protruding splinters smooth.

• Leave for another day.

• After a day fill the pond with water and check for leaks.

• Repeat two to three times.

Koi Pond – Concrete block filter units is a post from: DIY Guides

Koi Pond – Vortex filter chambers

Tom — Sun, 07 Jun 2009 17:01:35 +0000

Vortext chamber work just like a pre-fabricated chamber or fiberglass chamber, save for the difference in shape. The principle behind the shape of the chamber would have been discussed in an earlier chapter (see Vortex Chamber) and applied in the same manner to multiple vortex filter chamber like the one you see below.

Square filter bays then to hold dead water in the corners, so circular vortex chambers were then also used as filter chambers. Because of the movement of the water flow that goes around the walls of the chamber, it is said that debris and waste tend to move towards the drain located at the bottom of the chambers.

The image above shows 3 vortex chambers joined together and are similar to the fibreglass chambers we have already seen except for the shape.

On the left most chamber is of course Flocor, middle chamber holding JapMat, and the right most is the settlement chamber where the water from the pond enters.

These chambers are also free standing units which can be added to the system as desired, and can be obtained in different sizes to suit the size of the pond.

Koi Pond – Vortex filter chambers is a post from: DIY Guides

Koi Pond – Fibreglass filter unit

Tom — Sun, 07 Jun 2009 16:59:56 +0000

When choosing your fiberglass filter unit, take into account the surface area of the filter in relation to the surface area of the pond. The surface area of the filter has to be one third the area of the pond to work effectively.

Water from the pond enters the unit from the right most chamber where you can find filter media such as Flocor (pictured above).

The three 4″ pipes are the connections to the three bottom drains.

The middle sections contain supports for the media trays, which are flat and lay over the top. You do not need this tray if you’re using matting, but if you’re using heavy media like Alpha-grog then you do.

The left most chamber contains brushes.

In the last bay there should be suction for the pond pump. This should have some type of basket so that leaves, debris, or filter media is not drawn in.

Installing a fibreglass filter unit

If you plan to install a large fiberglass filter unit, remember that you will need to stand the unit on a level concrete base with the correct height. This is because the level of the water in the pond is influenced by the final height of the water in the filter (with the vortex chamber if you want to fit one in).

They do not need to be filled around outside as are meant to be free-standing.

The concrete base that you use should be the same mix as the pond base, and that is 3 parts chippings, 2 parts sand, and one part cement. Lay 6 inch deep concrete reinforced with mesh.

Koi Pond – Fibreglass filter unit is a post from: DIY Guides

Koi Pond – Filter systems

Tom — Sun, 07 Jun 2009 16:59:02 +0000

Knowing which filter system you will be using is important. You will need to make sure that you have a system that can support the volume of your pond effectively. You will also need to decide this base on the space that you have available to support the pond. There are a few types of systems available and they can be roughly broken down to these few:

Prefabricated multi-chamber systems.
Vortex units.
Home made filters from concrete blocks waterproofed with G4

You will also have to make sure that you have enough space in your garden to support the size of the filter system itself.

A typical 2 bay filter system supports up to 1000-1500 gallon ponds, a 3 bay system supports 1500-2000 gallon ponds; while a 4 bay system supports 2000-2500 gallon ponds. Consult the supplier and let them know what you need the filter system for, as they would be able to advise you on the best one that is suitable for your pond.

Prefabricated multi-chamber systems

Prefabricated multi-chamber systems come ready built. All you have to do is just provide them with the space to install it.

The figure below gives you a general idea about the layout of a 3 bay filter system, which is typical for most of the different types of system available, except for the Nexus unit.

Water enters the system from the vortex or the settling tank then goes to the bottom of the first chamber. It then raises through the filters right up to the top, then overflows into the second chamber. This then repeats with the 2^nd chamber into the 3^rd. From the third bay it is then pumped back into the pond. Any solids that enter the system will then slide down towards the bottom drain and flushed away.

Koi Pond – Filter systems is a post from: DIY Guides