|
Spring, The Critical Time
From March, 2003 NFKPC News Letter
We are all eagerly awaiting the coming of spring, but this is the most dangerous time of the year for our wet pets. At the present time, cold-water temperatures help to keep bacteria and viruses in check. But as the temperature rises, the bad "bugs" become active. The unfortunate coincidence, is that at the early spring water temperatures the fish immune system is at its weakest. Impeccable water quality standards will be the front line defense along with following good nutrition principles.
The two big medical problems on the horizon are Koi Herpes Virus (KHV) and Spring Viremia of Carp (SVCV). SVCV has not had much of an impact on the US hobby yet but it could become a very serious problem in the future. It is very contagious and has wiped out total fish populations in European carp farms.
KHV on the other hand, is here. Two major U.S. dealers of expensive Koi have recently discovered KHV in their stock. Before it was discovered, fish had been shipped to customers who experienced large kill rates when placed in warmer ponds. KHV is dormant in water below about 60 degrees F. but becomes active as water temperatures approach 70 degrees. As with other herpes viruses, if the fish survives the initial attack, that doesn't mean you are "out of the woods". And that presents the seriousness of the problem. You can buy a fish looking perfectly healthy but it could be a carrier of the virus. When the fish is stressed, the virus comes out of dormancy and lesions appear. Through the lesions, the virus is shed to other fish in the population.
What is the answer? A GOOD QUARANTINE SYSTEM IS VITAL! It won't do much to help a diseased fish but it can protect the rest of the pond population. Quarantine any new fish and, ideally, any returning fish that has been out of the pond (such as for a show). Fish should be quarantined at a water temperature in the mid 70's degrees F. for a minimum of 2 weeks, preferably longer.
The quarantine tank should be durable, deeper than wide, and hold at least 100 gallons. You will need to have some method of covering the tank to prevent the fish from escaping (they will jump amazingly high. There should be a submersible heater of 300 watts to bring the temperature to 74-76 degrees F.
Aeration is quite important.
The quarantine tank must have a filtration system and it should be functioning before the fish is introduced to the tank. There should be daily tests of both the pH (keep at or above 7.4) and the ammonia levels. Non-iodized salt can be added at the rate of 1 Tablespoon per gallon, or 2 ½ pounds per 100 gallons. This will make a 0.3% salt solution, will not stress the fish and will kill many parasites.
Hiding places for the fish should be provided. This can be accomplished by placing a large piece of PVC pipe cut into a half cylinder section on the bottom of the tank. You can also create a hiding place by floating large pieces of Styrofoam on the surface.
The extra work involved in going through a quarantine ritual is reward in itself if it turns out that the fish you would have introduced into your pond system is a carrier of parasites or worse yet, bacterial infections or viral infections such as KHV or SVCV.
|
