-Warning long-
Biosecurity
I'm an agriculture student (insert boo's and hick jokes from the audience). There are a lot of topics about the validity of various cycling methods, from fishless, to mature media, to <shudder>
LFS media gunk. Now I'm going to bring a concept to this debate that no-one has bothered to explain. One that the Ag industry is huge on. This concept is known as bio-security.
It's a great concept. Google it there are a lot of different ways to go about it. I'll just discuss the ones that are relevant to aquaria.
You could equate an aquarium to any intense agricultural system (see Pork and Chicken industries). You have a controlled environment, you can control what goes in, (what stock, where you got them, what tools, your hands, ect.), you control what goes out, (fry, shared tools, you're hands, whatever).
When you get a new tank you clean it, sterilize it (unless brand new), you set it up (gravel, plants, whatever). So now (no used filter or media) you have a little sterile world (minus any transfer from your hands.) So where do these little infections, and bacteria, and diseases come from?
1) Your stock, your fish will bring in all the bugs that are where-ever they came from. Parasites, worms, bacterial, and viral.
Now this is something that can be dealt with. You verify your fishes health. Got them all from the same store? Dump em in they’ve all got the same bugs.
Got them all from different places, then you have an issue. If you dump them in than that fish you got off aqua-bid that you imported from China? We'll it's immune to the bug that it's carrying, but the fish you got from your neighbor, well it's not. And it's also carrying a parasite from its old tank. And all the LFS fish have a strange viral infection that won't show any symptoms for the next few weeks. You wanna dump them all in together? Go ahead, you'll have to treat everyone in the tank, and will likely have a number of dead fish in a few weeks but you know that's your choice.
QT them? Now this is helpful. You're friend mentions to you that he's dosing his tank for Parasites so you can dose the fish you got from him. The LFS fish begin showing symptoms and getting extremely ill and dying? You can try to treat them and pat yourself on the back that it's only them that are sick. You're fish from China isn't showing any symptoms? That's fine, at the end of QT period when all the fish are happy and no-longer stressed from being shipped and transported, their immune systems will be on high power and able to fight off his bug better.
2) Your water.
You might have thought that it was safe but it's not, there are all sorts of little microbes and bugs that live in your pipes, they didn’t don't get knocked out by the water treatment plant when they went through etc. How do you deal with them? Well healthy fish will have healthy immune systems. Healthy immune systems will fend off all the opportunistic little bugs in your water without issue. Your water also carries nitrifying bacteria. There might not be very many of those guys in there but once they find a food source they can grow like crazy! Maybe not the speed of E.coli in ideal conditions (population doubling time approx. every 12 hours) but they'll from 1-millions pretty quick.
3) Food.
Anything that goes into your aquarium has the possibility of causing infection. Live foods are well known for this. Also sometimes frozen foods may also be a concern, as the freezing process may not get rid of all the nasties that had lived in the food when it was alive.
4) You.
That's right you can make your fish sick. That water vac you use on all your tanks on WC day? Well it's almost as good at spreading disease as if you moved one fish to a different tank every time you do that. For a non-aquatic example, there was a Foot and Mouth outbreak on a single farm in an area. It spread almost a 100 km to another farm, how? It hitched a ride on a farm hands clothes.
Biosecurity and cycling: Fishless cycling? Best option ever for cycling your tank from a bio-security stand-point. You can use
ammonia to sterilize your tank (will get the exact
PPM for that to you) so pure ammonia in the bottle will probably kill anything that tries to live there.
Using mature media/gravel?
1) From your own tank.
- this is fine, that means that any infections etc. that are living in your tanks currently will just be transferred to the new tank. Not a big deal provided that you're not having an active disease outbreak in it. One thing to keep in mind is that unless you sterilized you tank after a particularly nasty bug you had a few months ago you're stock may have developed immunity but it could still be lurking around in the media ect.
2) From another fish-keepers, or a friends tank.
- I wouldn't just my
. However you'll have to keep in mind that the same rules will exist. Except that you don't really have any way of verifying the health status of the tank that you're getting the media from unless you know it really well. Do they QT? Did they just get a fish that's harboring a nasty bug and their tanks not showing symptoms yet?
3) From the LFS.
- This option is so bad; I wouldn't even consider it but allow me to explain. Shipping, transport, and handling, stress fish. Any animal really, but fish are a big one. Stress suppresses the immune system (that's why college kids get colds during finals for example.) A suppressed immune system means that all the little bugs’ etcetera that the fish wouldn't be bothered by normally see this stressed fish with big neon welcome sign spray painted across them. They go to town and have a party. Usually this fish will continue to be stressed out during its LFS stay. It will likely be crowed, be in unideal tanks, exposed to new diseases constantly, perhaps improper food, and many other things. Tanks of stressed fish make the ideal breeding grounds for infections and infectious agents. This is particularly bad for places with communal filtration. The tank you're getting fish out of might look healthy but if nothing else the feeder fish tank has something brewing in it.
So you want to bring all of this into your nice new, clean sterile tank? I didn't think so.
4) Bacteria in a bottle:
- Tetra Safe Start, Bio-spira, ect.
- A great way again from a bio-security standpoint. The issue here is ensuring that you have 1) aquatic bacteria (i.e. not Cycle). 2) that the viability of these bacteria hasn’t been compromised. (At some point in its existence the bottle hasn't been cooked or frozen or left un-refrigerated ect.)
So moving on to the real world facts of bio-security in aquariums:
In an ideal biosecurity world all stock travels from most healthy places to least. It’s a one way flow so the animals coming in are always healthier then the animals already there. Now this doesn’t work in the aquarium industry all the time, mostly due to this place called the LFS. The LFS is sort of like an auction mart. Sure some of the animals in there may be healthy but due to stress compromised immune systems they don’t usually leave that way. So since most of us buy our stock from the LFS what can we do? We’ve got our tanks cycled and healthy. How do we bring these sick fish in? Well one way is the QT tank as has already been mentioned. While you can argue the pros and cons of it, it is probably the best tool that we’ve got. It allows us to verify the health of our new fish without infecting our old ones. It allows the new fishes immune system a chance to reboot and recover, and it allows us to treat if we need to. If the fish is a disease carrier (it carries infection without any external signs) then the QT tank can’t help us there. In that case the best we can do is ensure that the tank any new fish goes into is as healthy as we can make it so that our fishes immune systems can handle whatever he is carrying.
Stress and disease:
Stress suppresses the immune system. All hobbyists can tell you that it’s the fish that are stressed in their tanks that are most likely to get ill. Everyone has noticed in their regular lives that when you’re under stress you’re more likely to get sick. Transporting and handling fish causes stress but so too can improper tank conditions. A fish that is being bullied is being stressed. A fish that is in too small a tank is being stressed. A lone schooling fish is being stressed; a group of territorial fish that like to be alone are being stressed. Bad tank water is a cause of stress, which is why it’s good to test it regularly.
So other then getting sick why is stress bad? Well it has to do with the nature of disease. You see there’s a great quote from one of my professors, “Dilution is the solution for pollution.” Unless present in sufficient amounts most pathogens won’t cause problems. (I believe the smallest amount for even particularly contagious pathogens is still in the 100’s-1000 of organisms). So while you might have a lone piece of virus floating around looking for a host it won’t cause problems since the immune system can fight it off. However if a fish has a compromised immune system then perhaps instead of 1000’s of the pathogen to cause infection you only need half that. And once the pathogen sets up shop in your stressed fish your fish can become a little factory. And suddenly you tank is just full of copies of this pathogen in large enough numbers that that healthy non-stressed fish start to get sick… Sometimes fish who are dormant carriers of the pathogen will get stressed and the pathogen will begin to replicate itself and the carrier will secrete it into the environment even though it shows no signs of being ill itself. When you start to think on this it’s amazing our fish are as healthy as they are.
Biosecurity recommendations:
Not everyone can have a perfect bio-security system but here are some things that you can consider:
Aquarium tools: Don’t share between tanks.
·If possible get every tank its own gravel vac etc, if that’s not possible then instead of doing all your tanks in one day do tank maintenance on each tank as spaced out as possible. Rinse the gravel vac well under clean water and allow to dry between tanks.
·Use a net dip between tanks if you can’t let your fish net dry between uses, especially if you’re working with ill of infected fish.
·Have 2 pails, one for adding water to tanks and one for taking it out. That way water residue in the pail can’t carry pathogens from one tank to another.
Management: - ·Wash your hands between tanks.
- ·QT fish and bleach dip plants.
- ·Isolate sick and or injured fish promptly to treat. A sick or injured fish is a stressed fish a stressed fish can become a pathogen factory.
- ·Minimize stress: try to keep fish in as ideal an environment as possible, research tank-mate compatibility. Remove stressed fish from the tank/take action to help decrease or remove the cause of the stress.
This list isn’t a set in stone do or die sort of thing. I wrote it to be as informative as possible and to make you aware of some of the issues. The key to keeping tanks healthy is prevention. It’s the cheapest pro-active treatment possible and the key to prevention is biosecurity and being aware or the risks. I hope that you found it interesting.
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