Quarantine. "An ounce of prevention."


Apr 21, 2009

“An ounce of prevention” - how the old adage applies to the keeping of healthy stock for both professional and amateur today

Contributed by the Calypso Fish & Aquaria Club, London, England – “Although we are uncertain as to the exact source of this article it is to be credited to Anthony Evans, who was the original publisher (PetFish) and probably the author. It is over ‘quarant’ years old but as applicable today as the day on which it was written."

Undoubtedly the best method of keeping the aquarium disease and trouble free is to avoid introducing troubles into it. An obvious remark, you might think, but the practical details involved in conforming to this rule are all too seldom observed sufficiently rigorously by fish-keepers. It all means taking great care and being aware all of the time what dangers are constantly threatening the health of the aquarium's inmates.
Imported fishes are frequently parasitical, and although their parasites may cause them only minor inconvenience whilst the fishes are in their natural wide open spaces, in the confined volume of the aquarium water the parasites can increase to an extent that will cripple and probably kill their hosts. This problem will always be with us, so it must be faced by regarding any newly acquired fish as a potential purveyor of disease to your tanks. Not until you are sure that it is in fact quite healthy should it be placed with your present stock.
How can this clean bill of health be assessed? Only by subjecting the new fish to a period of quarantine. To say that an animal is in quarantine does not mean that it is diseased, only that it is isolated under observation to ensure that it is not so affected. If it does prove to be unhealthy, treatment can be given to cure it and restore it to health. Another advantage of the quarantine procedure is that fishes received in an undernourished state, as newly imported specimens frequently are, can be given a special feeding routine to build them up before they are subjected to the intense and vigorous competi*tion for food that can go on in a well-stocked community tank, for example.
Point number one about quarantine, then, is that the new fish must be isolated. Obviously, several new fishes from the same source can be kept together for the quaran*tine period, but it would be adding to your risks to place together fishes from separate sources.

What are the details of the procedure to be used?

A quarantine aquarium can be kept for all new stock. How big it should be depends on the maximum number and size of fishes you are likely to be receiving. Over*crowding must be avoided. An 18 in. by 12 in. by 12 in. or a 24 in. by 12 in. by 12 in. tank would be suitable for the average fish-keeper. The tank should not be fur*nished in the usual meaning of this term. It need contain no more than the water, the heater and the thermostat, but for the comfort of the fishes, if the aquarium base is of glass and is not blacked out, a thin layer of coarse grit can be included. No special lighting is required, but an inspection lamp should be used overhead for a thorough check each day to be made on the quarantined stock.

Point number two to be given emphasis concerns the period of quarantine. The word itself originally denoted a period of 40 days, but it was not coined exclusively for aquarium application! Experience shows that nothing less than 10 days is safe, and 14 days is a time giving almost full security. That is to say, if a new fish is behaving normally, swimming actively, feeding readily and bearing no external visible signs of disease such as blotches, lumps or spots after 14 days in the quarantine tank you are unlikely to be introducing disorders to the healthy tanks if you then transfer it there.
Commonsense has to be used in this matter, however. If several fishes in a batch undergoing quarantine were to die during the period it would be wisest to extend the isolation time beyond 14 days, even though the remain*ing specimens seemed to be well. Be wary, too, if fishes that seem otherwise well keep flicking against the bottom grit or the heater wire. They are showing signs of irritation that may mean parasites are present.

Water temperature in the quarantine aquarium is best kept in the upper seventies or at 80F (26-27C); this will encourage early manifestation of symptoms if hidden disease is present and will also promote the liveliest behaviour that the fishes should be capable of showing.

Keep the quarantine tank clean. The siphon tube (for use exclusively in the quarantine tank) should be used over the bottom to take out sediment at least once during the 14 days, and about a bucketful of water should be removed and replaced by fresh water, if several fishes are in the tank. This is because in the absence of plants the water can become overcharged with soluble waste matter from the fishes. On the whole it is best not to include a chemical in the quarantine tank water as a routine, so that if a recognisable disease does break out the proper chemical cure can then be used. It is never a good procedure to have a mixture of different chemicals in the water.

Water plants can be a vehicle of disease for the aquarium if they have come freshly from an affected tank, and ideally new plants should undergo a quarantine period in a tank without fishes. However, many fish-keepers find that they can avoid trouble from this source by giving plants several rinses in clean water; some add weak disinfectants such as potassium permanganate or sodium hypo chlorite to the water used for the first rinses.

Use of the quarantine procedure is probably a counsel of perfection that will not be followed by the man who has only a single community tank, and this is unfortu*nate since such a man is more likely to be discouraged from the hobby by persistent losses through disease than is the keeper of several tanks. For the latter type of aquarist, however, the quarantine system should be an accepted and never to be neglected routine.


Author: Anthony Evans
Title: Quarantine. "An ounce of prevention."
Summary: The importance of quarantining new fish. The procedure: the quarantine aquarium, period of quarantine, water temperature, cleanliness. How to rinse new plants.
Contact for editing purposes:
email: editor: gerald@calypso.org.uk
Date first published:
Publication: Petfish magazine
Reprinted from Aquarticles:
2004: Posted on thefishworld.co.uk
Sept. 2005: Posted by Mike Talbot, of England, as part of the database of his msn group: africanriftlakecichlids.
Sept. 2005: ARVAS Digest, Allegheny River Aquarium Soc. ARTICLE USE:
Internet publication (club or non-profit web site):
1. Credit author, original publication, and Aquarticles.
2. Link to http://www.aquarticles.com and original website if applicable.
3. Advise Aquarticles
Printed publication:
Mail one printed copy to each of::
Gerald Jennings,
c/o Calypso Fish and Aquaria Club.
2 Gatcombe Road,
London N. 194PT
#205 - 5525 West Boulevard
Vancouver, British Columbia
V6M 3W6
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