For many pond enthusiasts the arrival of spring can cause many problems. Here we hope to help you prevent as many of these problems as possible and prepare for the up and coming season of 2008.

The main cause for concern as the spring starts is the rise in water temperatures and the problems this can bring with it.

Unless as a pond owner you have intervined with the Koi's natural instincts to rest over the winter months by installing a heater to keep the water temperatures above 8 degees c all year round you will have discovered your Koi become relatively "Inactive" and stop eating for the winter.

Whilst the Koi rest in the colder months their immune system tends to slow down, this at the time is no cause for concern as parasites don't tend to be present in such cold climates, however as the weather warms up in spring the parasites start to appear and warmer climate helps them to grow and multiply in the pond and on the Koi, who's immune systems are only rebuilding them selves for the Summer and are not yet forcefull enough to fight of the parasites.

How To Accomodate Your Koi Over Spring...

There are ways during the spring you can help your Koi to prepare for the Summer and rebiuld their immune system,

• Start adding oxygen to the pond - You can do this by adding air stones directly into the pond or into the filter itself...This is also a good idea when treating for the parasites as many treatments cause Oxygen levels to drop which will result in Koi gasping for air.
• Keep a close eye for your Koi being distressed - Ulcers and sores can upset the fish causing them to become stressed.
• Feed the fish on a medicated food to boost their immune system - Remember do not overfeed, if the Koi have not been fed over the winter months then they will need time for their digestive system to start to function fully again - Overfeeding will cause Nitrite levels to rise - It may also be an idea to mix the medicated food with a wheatgerm food which is easier for the Koi to digest.
• Test the pond water regularly - by keeping a close eye on the water levels you will be able to find out if there are problems in there.

How To Determine If You Have Parasites

The most improtant thing to remeber before I tell you what to look for in your Koi is that not all koi will have the same reaction to a parasite living on them and it is improtant you treat the effected pond not just the Koi who seems to be experiencing a parasite presence.

• Rubbing/Scratching/Flashing - Koi will tend to do these things to try to "shake off" the parasites - Remember this will be causing the Koi to become stressed.
• Jumping - Again Koi will jump to try to remove the parasites from them selves - This can be dangerous to the fish as they may land either on a Rock at the side of the pond or out of the pond completly.

Diagnosing Your Koi

There are two main types of parasites to be looking out for these are The Macro Parasites and The Protozoans.

The Macro Parasites include

• Lernaea - Lernaea which is more commonly known as Anchor Worm due to it's head shape and technique of attaching it's self to a Koi, is a parasite which is visable to the naked eye, they usually measure 10-12mm in length. The Lernaea burrows it's head under the scale of a Koi and 'Anchors' a hold leaving the body and tail visable. Lernaea is a egg layer and live bearer. 
• Dactylogyrus - Dactylogyrus which is more commonly know as The Gill Fluke is again another egg layer and live bearer, they range in size fom 0.5mm upto 3.0mm in length. Dactylogyrus are characterised by there large grappling hooks which they use to attach them selves to the Koi.Gyrodactylus - Gyrodactylus is a  secondary bacterial infection caused by the physical damage of the Dactaylgyrus.

• Argulus - Argulus more commonly known as The Fish Louse, is said to be introduced into ponds by frogs and toads. The Argulus can be detected with the naked eye due to the colour of them standing out against the White on a Koi. The vary in size from 1mm - 5mm. The Argulus uses it's suckers to attach it's self to the Koi causing damage to the skin, it then furthers it's self by injecting poison into it's victim which can cause inflammation and bleeding, there is then a potential risk of a secondary bacterial infection.

The Protozoans Include

• Chilodonella - Chilodonella Is thought to be the most dangerous of parasites and causes mass fatalities particullaty in overstocked ponds. The Chilodonella is only very tiny and a microscope will be required to identify it. The Chilodenella is a reproducer, the adults are usually a heart shape, this can chan=ge though. Chilodonella can swim short distances so will latch onto healthy Koi swimming around the pond. If a koi has an infestation of Chilodonella then the skin will fast turn opaque particullatly between the head & dorsel fin. Gills can also be attacked and quickly destroyed causing the death of the Koi.
• Costia - Costia effects both the skin and gills of Koi, it reproduces itself by binary fission (Binary fission is the form of asexual reproductionin single-celled organisms by which one cell divides into two cells of the same size.). In many cases Costia is seen as a secondary bactrial infection. Once a Koi is infected you will notice clamped fins, rubbing and flashing and the skin may to have a Grey/White Opaqeness. Costia tends to be found in coldeer waters.
• Trichodina - Trichodina will again need to be under a microscope to detect, once there youwill know if it is Trichodina as it is a distinctive parasite. Trichodina it perfectly round and is covered in tiny hooks which resemble Cilia. Trichodina constantly rotates as it moves through mucus causing tissue damage, the oi will also start to show a Grey/White opaqueness to the skin. Trichodina can live for some time in the water without a Koi.
• Ichthyophthirius - Ichthyophthirius calso known as Ich or White Spot can be detected by the naked eye on any of it's victims. Ich leaves tiny white spots on the skin in an effected area of the Koi. Ich will attack the body of a Koi howeverthe main areas for attack are dorsal and caudal fins. White Spot Swarmers  - Swarmers are created when the adult falls from the Koi, surrounds itself in a capsule and attaches itself to a rock or plant. Whilst in the capsule the Ich divides itself over and over until there are between 250 & 1000 swarmers which are then released and swim off to attack the Koi, opnce on the Koi the swarmer turns into an adult and becomes an Ich (This process) can take upto 10 weeks to complete.

There are treatments available for the above parasites which can be found on our web site www.koicarp.netalong with more details on the parasites.

Please keep watching for more tips next month