pcsb23
04-29-2010, 04:23 PM
Quarantine - What is it and why should we do it?
I am often asked about quarantine and mixing fish from different sources. These questions are often asked on the forum too. These are my thoughts and my methods, which I hope are of some use.
From wikipedia ...
Quarantine is voluntary or compulsory isolation, typically to contain the spread of something considered dangerous, often but not always disease. The word comes from the Italian (seventeenth century Venetian) quarantena, meaning forty day period.
To truly quarantine (qt) fish we really need separate facilities and we also need to practise extremely high bio security. In a very simplified explanation, we need to thoroughly wash and put on clean clothes before we enter the qt facility and after we leave it. This facility would also have threshold protection which could involve air locks, foot washes, spray arches etc ...
So what can the average hobbyist do? I'm not aware of any that have the resources or time to do the above, perhaps we should just not bother?
I for one always qt new fish, no matter where I get them from. I don't believe that it eliminates risk, but it certainly significantly reduces it, and sometimes that is the best we can do!
Perhaps a better way of looking at this would be to consider what can be achieved by following some simple guidelines when adding new stock to our existing.
So to go back to the first part of the original question ...
Quarantine - What is it? In practical terms it is isolating the new fish in a separate tank for a given period of time, and as the word "quarantine" was derived from the Italian meaning forty day period that would seem to be a good number to go with, I personally qt new fish for a minimum of six weeks, which is coincidentally 42 days. ;)
So how do we practically isolate fish? Well it goes without saying (I hope!) that we need to use a separate tank with it's own filtration and heating. This tank should be as far away as possible from the existing stock, if you can do this in another room so much the better. However most of us are somewhat restricted by space so ...
What isn't always obvious is that any equipment used on the qt tank must be dedicated to that tank, e.g. nets, syphon hoses, towels etc. There is not much point qt'ing fish if we immediately put our hands into the existing tanks after working on the qt tank either! I have surgical hand scrub in the fish room which at least gives me a second chance!
As for the second part of the question ...
Quarantine - why should we do it? There are many reasons. Not the least of them is to avoid introducing disease. But the introduction of disease is a two way street, meaning the new stock may catch something from the existing stock.
When a fish is transported, even short distances, it goes through quite a stressful time. It's own hormone levels will go up and down, it's immune system will go into overdrive then almost shutdown. It will be subjected to temperature changes, chemical changes and toxins (ammonia etc). There could even be an O2 shortage depending on bagging method / time etc. In short the fish is compromised and any opportunistic pathogen now has an opportunity to take hold.
Putting new fish into a qt tank gives us the opportunity to treat or deal with any opportunistic attacks. It provides a safe environment for the new fish to recover and get their immune systems back online. It allows the fish to recover from the stress of shipping.
It is possible that each set of fish have been exposed to different pathogens and have built immunity towards these, but have little or no immunity to each others. A bit like a one of us going into a rain forest and finding a lost tribe, the common cold is just an inconvenience to us, but it will kill the people from the tribe - far fetched? not really as history tells us it has happened.
Russian Roulette - There are some that never qt and they always tell me they have never had a problem. In my early days with discus I too never qt'd fish, and for some years I got away with it too. Then once it bit me, the result was carnage. Some believe it will never happen to them, I used to believe the same too.
My quarantine method - I usually have to qt new fish in my fish room, this presents me with some challenges, the tanks are tow tiered and are fairly close to each other not being the least of them!
Before the fish arrive I will clean a tank out and take it off the system, removing the down pipe from the fill valve too when they would normally touch the water. I usually also fit an upturned 90 degree bend on the outlet too to try and avoid any water going down to the sump. The tank will have a heater and a sponge filter. On top of the tank I will have a syphon tube and a towel nearby.
I have a centralised air supply, but the intake is out side of the fish room, this allows me to use this supply in all tanks and minimises the risk of literally pushing airborne pathogens into the various tanks.
The sponge filter will be matured and will have been matured on the system. It will therefore have been exposed to anything that my current stock has. I do not have the time or facilities to cycle a sponge filter using a fish-less method. I believe having a properly cycled sponge outweighs the risk.
As mentioned before I have surgical hand scrub available too.
I do not make my water like that of the supplier, although I have done in the past. The reason I don't is that by the time the fish arrive home the water they are in is significantly different to that they came from anyway and is at best poor quality, at worst it is lethal once the bag is opened. The ammonia levels in the bagged water will be off the scale and once air gets to it in 99% of cases the water's pH goes up making the ammonia toxic.
I will ensure that all tank covers are closed on the existing tanks, and if I am putting the new fish into a top tier tank I will have a clean towel covering the tank below it. I have usually allowed the temperature in the qt tank to drop to around 23 to 24c as most times the shipped fish arrive in colder water.
I get a clean bucket with a clean net over it, open one bag at a time and drain the water from bag straight away, keeping the neck sufficiently closed as to not allow the fish to slide out. The reason the net is there is for the odd time when I do :o Once the water is drained the fish is then slid straight into the qt tank. The empty bag is then discarded. I repeat the above until all the fish are safely in the qt tank. Using this method I have never lost a fish, nor have I ever had one showing ammonia burn.
There is often debate as to whether the new fish should be treated prophylacticly - I guess the answer to this really depends on the quality of the source or if they are wild caught and have not been "cleaned" prior to you getting them. There is a good argument for immediately using a product like acriflavin, formalin and malachite green (F&MG) or potassium permanganate (PP) as a one off bath. That argument is that it will deal with any surface and water borne opportunistic pathogens. I have on occasion done so myself, though my usual practise is to use nothing more than clean water. I never, ever use salt on new fish.
As I would never get domestic fish from a dodgy source any further prophylactic treatments are unnecessary. It is different with wild caught, as some times these arrive in poor shape. In these cases I use F&MG on arrival. Then I will treat with flubendazole, this is a gentle but effective wormer. That is the limit of any prophylactic treatment I do.
Any further treatment is determined by how the fish respond whilst in qt. I usually take scrapes to check for flukes and the like. I will also collect fresh faecal samples and check that for any sign of internal parasites.
I always try to deal with the qt tank after I have dealt with the existing stock. I always wash my hands and arms before going in the qt tank and after I have finished. I either use anti bacterial soap or use the surgical hand scrub. I make sure that any spilt water is wiped up straight away, any that goes onto the floor gets moped up - I usually have a mop with bleach in the fish room (I am always spilling water and overflowing something or other :o).
Inevitably both sets of fish will be exposed to whatever the other may be carrying, many bacterial infections are transmitted via air. In some ways this isn't a bad thing as the exposure will be at very low levels, at least initially anyway.
Quite often people will say something like "but all my fish come from the same source - so why should I bother with qt". Well if you only have fish from one source, and that source only gets fish from one source then I would agree that you could do away with qt provided there has never been any risk that any pathogen has been introduced. That means absolutely no other freshwater organisms of any sort have ever been introduced into your system, no BN's shrimp, angels, rams etc, etc... Most of us keep more than discus so to answer the above - qt them!
It is also important to understand that the majority of imported fish come from more than one source. This is a simple fact and should not deter people from buying these discus. And even when they come from a single source once they at the dealers then in 99% of cases they are exposed to pathogens from multiple sources.
Another common question is "can I mix Asian and German (usually Stendker) discus" - again many will say no. Why is that? Personally I think that it is nonsense. I have Asian and Stendker discus in the same tanks and on the same system. Whilst most of my collection is Asian, I still have a dozen Stendkers as well as the eight challenge fish. If I see a nice discus I will buy it and it will be mixed in with my existing stock. I have also had wild caught discus on the same system as my other discus.
I buy fish to mix together, so sooner or later the new fish must be introduced to the existing stock. I use what is commonly called a sacrificial lamb to do this. I will take a healthy fish from my existing stock and put it with the new fish. If I have a lot of new fish then I will take an apparently healthy new fish and put it together with the sacrificial lamb in a separate qt tank. If there are going to be problems these are usually seen within a few days, if after two weeks the fish are fine then I am happy to mix them.
Like all discus keepers I do from time to time get problems, but in all honesty it is very, very rare these days. I have been using (and refining) this method for many years and so far it has proven to be successful. If you follow my method I cannot guarantee you won't have problems, but you will be taking a sensible and practical approach to minimising the risk of adding new stock.
Hope this is of some use, and I hope it allays some of the fears about adding new fish, no matter where they come from.
I am often asked about quarantine and mixing fish from different sources. These questions are often asked on the forum too. These are my thoughts and my methods, which I hope are of some use.
From wikipedia ...
Quarantine is voluntary or compulsory isolation, typically to contain the spread of something considered dangerous, often but not always disease. The word comes from the Italian (seventeenth century Venetian) quarantena, meaning forty day period.
To truly quarantine (qt) fish we really need separate facilities and we also need to practise extremely high bio security. In a very simplified explanation, we need to thoroughly wash and put on clean clothes before we enter the qt facility and after we leave it. This facility would also have threshold protection which could involve air locks, foot washes, spray arches etc ...
So what can the average hobbyist do? I'm not aware of any that have the resources or time to do the above, perhaps we should just not bother?
I for one always qt new fish, no matter where I get them from. I don't believe that it eliminates risk, but it certainly significantly reduces it, and sometimes that is the best we can do!
Perhaps a better way of looking at this would be to consider what can be achieved by following some simple guidelines when adding new stock to our existing.
So to go back to the first part of the original question ...
Quarantine - What is it? In practical terms it is isolating the new fish in a separate tank for a given period of time, and as the word "quarantine" was derived from the Italian meaning forty day period that would seem to be a good number to go with, I personally qt new fish for a minimum of six weeks, which is coincidentally 42 days. ;)
So how do we practically isolate fish? Well it goes without saying (I hope!) that we need to use a separate tank with it's own filtration and heating. This tank should be as far away as possible from the existing stock, if you can do this in another room so much the better. However most of us are somewhat restricted by space so ...
What isn't always obvious is that any equipment used on the qt tank must be dedicated to that tank, e.g. nets, syphon hoses, towels etc. There is not much point qt'ing fish if we immediately put our hands into the existing tanks after working on the qt tank either! I have surgical hand scrub in the fish room which at least gives me a second chance!
As for the second part of the question ...
Quarantine - why should we do it? There are many reasons. Not the least of them is to avoid introducing disease. But the introduction of disease is a two way street, meaning the new stock may catch something from the existing stock.
When a fish is transported, even short distances, it goes through quite a stressful time. It's own hormone levels will go up and down, it's immune system will go into overdrive then almost shutdown. It will be subjected to temperature changes, chemical changes and toxins (ammonia etc). There could even be an O2 shortage depending on bagging method / time etc. In short the fish is compromised and any opportunistic pathogen now has an opportunity to take hold.
Putting new fish into a qt tank gives us the opportunity to treat or deal with any opportunistic attacks. It provides a safe environment for the new fish to recover and get their immune systems back online. It allows the fish to recover from the stress of shipping.
It is possible that each set of fish have been exposed to different pathogens and have built immunity towards these, but have little or no immunity to each others. A bit like a one of us going into a rain forest and finding a lost tribe, the common cold is just an inconvenience to us, but it will kill the people from the tribe - far fetched? not really as history tells us it has happened.
Russian Roulette - There are some that never qt and they always tell me they have never had a problem. In my early days with discus I too never qt'd fish, and for some years I got away with it too. Then once it bit me, the result was carnage. Some believe it will never happen to them, I used to believe the same too.
My quarantine method - I usually have to qt new fish in my fish room, this presents me with some challenges, the tanks are tow tiered and are fairly close to each other not being the least of them!
Before the fish arrive I will clean a tank out and take it off the system, removing the down pipe from the fill valve too when they would normally touch the water. I usually also fit an upturned 90 degree bend on the outlet too to try and avoid any water going down to the sump. The tank will have a heater and a sponge filter. On top of the tank I will have a syphon tube and a towel nearby.
I have a centralised air supply, but the intake is out side of the fish room, this allows me to use this supply in all tanks and minimises the risk of literally pushing airborne pathogens into the various tanks.
The sponge filter will be matured and will have been matured on the system. It will therefore have been exposed to anything that my current stock has. I do not have the time or facilities to cycle a sponge filter using a fish-less method. I believe having a properly cycled sponge outweighs the risk.
As mentioned before I have surgical hand scrub available too.
I do not make my water like that of the supplier, although I have done in the past. The reason I don't is that by the time the fish arrive home the water they are in is significantly different to that they came from anyway and is at best poor quality, at worst it is lethal once the bag is opened. The ammonia levels in the bagged water will be off the scale and once air gets to it in 99% of cases the water's pH goes up making the ammonia toxic.
I will ensure that all tank covers are closed on the existing tanks, and if I am putting the new fish into a top tier tank I will have a clean towel covering the tank below it. I have usually allowed the temperature in the qt tank to drop to around 23 to 24c as most times the shipped fish arrive in colder water.
I get a clean bucket with a clean net over it, open one bag at a time and drain the water from bag straight away, keeping the neck sufficiently closed as to not allow the fish to slide out. The reason the net is there is for the odd time when I do :o Once the water is drained the fish is then slid straight into the qt tank. The empty bag is then discarded. I repeat the above until all the fish are safely in the qt tank. Using this method I have never lost a fish, nor have I ever had one showing ammonia burn.
There is often debate as to whether the new fish should be treated prophylacticly - I guess the answer to this really depends on the quality of the source or if they are wild caught and have not been "cleaned" prior to you getting them. There is a good argument for immediately using a product like acriflavin, formalin and malachite green (F&MG) or potassium permanganate (PP) as a one off bath. That argument is that it will deal with any surface and water borne opportunistic pathogens. I have on occasion done so myself, though my usual practise is to use nothing more than clean water. I never, ever use salt on new fish.
As I would never get domestic fish from a dodgy source any further prophylactic treatments are unnecessary. It is different with wild caught, as some times these arrive in poor shape. In these cases I use F&MG on arrival. Then I will treat with flubendazole, this is a gentle but effective wormer. That is the limit of any prophylactic treatment I do.
Any further treatment is determined by how the fish respond whilst in qt. I usually take scrapes to check for flukes and the like. I will also collect fresh faecal samples and check that for any sign of internal parasites.
I always try to deal with the qt tank after I have dealt with the existing stock. I always wash my hands and arms before going in the qt tank and after I have finished. I either use anti bacterial soap or use the surgical hand scrub. I make sure that any spilt water is wiped up straight away, any that goes onto the floor gets moped up - I usually have a mop with bleach in the fish room (I am always spilling water and overflowing something or other :o).
Inevitably both sets of fish will be exposed to whatever the other may be carrying, many bacterial infections are transmitted via air. In some ways this isn't a bad thing as the exposure will be at very low levels, at least initially anyway.
Quite often people will say something like "but all my fish come from the same source - so why should I bother with qt". Well if you only have fish from one source, and that source only gets fish from one source then I would agree that you could do away with qt provided there has never been any risk that any pathogen has been introduced. That means absolutely no other freshwater organisms of any sort have ever been introduced into your system, no BN's shrimp, angels, rams etc, etc... Most of us keep more than discus so to answer the above - qt them!
It is also important to understand that the majority of imported fish come from more than one source. This is a simple fact and should not deter people from buying these discus. And even when they come from a single source once they at the dealers then in 99% of cases they are exposed to pathogens from multiple sources.
Another common question is "can I mix Asian and German (usually Stendker) discus" - again many will say no. Why is that? Personally I think that it is nonsense. I have Asian and Stendker discus in the same tanks and on the same system. Whilst most of my collection is Asian, I still have a dozen Stendkers as well as the eight challenge fish. If I see a nice discus I will buy it and it will be mixed in with my existing stock. I have also had wild caught discus on the same system as my other discus.
I buy fish to mix together, so sooner or later the new fish must be introduced to the existing stock. I use what is commonly called a sacrificial lamb to do this. I will take a healthy fish from my existing stock and put it with the new fish. If I have a lot of new fish then I will take an apparently healthy new fish and put it together with the sacrificial lamb in a separate qt tank. If there are going to be problems these are usually seen within a few days, if after two weeks the fish are fine then I am happy to mix them.
Like all discus keepers I do from time to time get problems, but in all honesty it is very, very rare these days. I have been using (and refining) this method for many years and so far it has proven to be successful. If you follow my method I cannot guarantee you won't have problems, but you will be taking a sensible and practical approach to minimising the risk of adding new stock.
Hope this is of some use, and I hope it allays some of the fears about adding new fish, no matter where they come from.