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| La faune marine |
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| La faune marine |
Débutants : Poissons d'eau de merIMPORTANT : Lisez la partie COPYRIGHT
Il est très facile de faire des erreurs lorsque vous mettez en route votre premier bac d'eau de mer.
Afin de préserver à la fois votre portefeuille mais aussi et surtout la faune marine, commencez seulement
avec quelques poissons peu onéreux et solides. La plupart des poissons marins sont collectés dans la nature
plutôt que d'être élevés, vos erreurs auront donc des impacts sur les océans !
Le meilleur poisson pour débuter l'aquariophilie marine est la demoiselle. Ces poissons sont très robustes, capables de résister aux pires conditions, ils ne sont pas difficiles à nourrir et ne coûtent pas trop cher. La contrepartie est qu'ils sont relativement aggressifs, un ou deux seulement pourront coexister dans un même bac. Il y aura de nombreux combats si vous en mettez plus. Les revendeurs en hébergent beaucoup plus afin qu'aucun n'établisse son territoire. Ceci ne peut être maintenu sur une longue période. Il vaut mieux démarrer un bac avec des demoiselles. Si vous ajouter par la suite des poissons aggressifs, vous pouvez soit conserver les demoiselles, soit les ramener au magasin.
Certaines demoiselles ne sont pas aussi aggressives que d'autres. La demoiselle bleue et les demoiselles à queue jaune par exemple. Tandis que les demoiselles domino et à trois bandes le sont. Dans tous les cas, la demoiselle est certainement le poisson avec lequel il est souhaitable de commencer.
Certains aiment bien démarrer un bac avec des blacks mollies acclimatés à l'eau de mer. Ceci a l'avantage d'être peu couteux et permet de se faire la main pour maintenir la salinité et le pH pour des poissons pas trop sensibles. Bien que ce soit une méthode sans risque, on ne peut aquérir une solide expérience marine de cette façon. Les Mollies sont poissons reproduits de manière industrielle et ne sont pas sauvages.
Si vous achetez des blacks mollies pour eau douce, vous pouvez les accclimater à l'eau de mer en ajoutant de l'eau de mer dans le sac sur une durée de 6 à 8 heures, en enlevant l'eau excédentaire lorsque celui ci déborde. Augmenter lentement la salinité permet aux poissons de s'habituer aux nouvelles conditions. Vous pourrez conserver les mollies dans le bac après la mise en place du cycle, mais n'importe quel poisson marin aggressif sera une gène pour les gentils mollies.
Les poissons clowns sont à rapprocher des demoiselles, et sont assez résistants. Cependant, ils sont beaucoup plus délicat à acclimater à un nouveau bac. Les Clowns, en général, sont très territoriaux, mais ne sont pas aggressifs envers les autres espèces. Ils peuvent se passer d'une anémone, ce qui est une bonne chose car l'anémone est très difficile à maintenir. Les anémones recquièrent une eau très propre et des conditions d'éclairage exigeante. De plus, chaque espèce de clown préfére certaines espèces d'anémones, et aucun d'entre eux n'acceptera d'élire domicile dans une de ces peu couteuses anémones des caraïbes, plus faciles à maintenir. Certains poissons clowns sont élevés.
Ces petits poissons sont assez robustes et ne risquent pas d'embéter les autres pensionnaires d'un bac. Certains ont beaucoup de caractère, mais ils seront perdu dans un trop grand bac. Nombreux sont ceux qui permettent de contrôler la prolifération d'algues. Cependant, certains se nourrissent en filtrant le substrat et sont donc difficiles à maintenir dans un bac ne contenant que des poissons (par exemple : le poisson mandarin).
Tangs are fairly hardy, though they are very susceptible to marine ich. Being algae eaters, they are useful to introduce when your tank starts growing algae. They must be fed leafy greens if there is no suitable algae growing in the tank (green algae). Many different tangs are commonly seen for reasonable prices.
If you are setting up a tank for large aggressive fish, you can start with triggers and/or lionfish, as they are hardy. However, mistakes with them can be very costly, so you may want to practice on less expensive and easier fish. Also, carnivorous fish such as triggers and lions should be fed plenty of shell fish and other marine life. Specifically, many people feed lions feeder goldfish. This is really a bad practice because goldfish are freshwater fish and do not provide the same nutrition that a saltwater fish would. Specifically, feeding saltwater fish freshwater food can cause premature liver failure and the early demise of your fish.
These are fish that must be ignored while in the pet store - all are both delicate and difficult fish to keep. Many butterflies have specialized diets which make them hard to maintain in captivity.
Batfish are also other fish that should be avoided.
Other saltwater fish which can be attempted once you get good at controlling the fish's environment are hawkfishes, grammas, dottybacks, basslets, and wrasses. Some are more difficult to keep than others, but not nearly as difficult as angles and butterflies.
All angelfish, all butterflyfish, Pipefish, Seahorses, Long-nosed Filefish, Blue Ribbon Eels, Stonefish, and Moorish Idols. Mandarin fish should also be avoided in non-reef tanks (they are hard to feed).
Many people believe that invertebrates are only for mini or micro-reef tanks. Not so. There are quite a few invertebrates that do well in non-reef tanks. However, not a lot of invertebrates should be attempted by inexperienced saltwater fish keepers. Below is a brief summary of the more hardy invertebrates available to aquarists.
There are many different shrimps available on the market, with most of them being perfectly suitable for a lightly loaded saltwater tank. In fact, some shrimps are more suitable for fish and invertebrate tanks than for a reef tank since they like to eat corals.
Some of the more popular shrimps are Cleaner shrimp Lysmata amboinensis, Blood shrimp Lysmata debelius, Candycane or Peppermint shrimp Periclimenes brevcarpalis, and Coral Banded shrimp Stenopus hispidus. The cleaner shrimp is denoted by a white on red stripe down the middle of its back. They are fairly inexpensive and easy to keep. They should, however, be kept in small groups (3-4), as this makes them more social and more likely to come out often. The Blood shrimp is intensely red with some white spots. It is a very striking animal, but usually commands a high price. The Coral Banded shrimp is very popular with reef keepers, but must be watched around small fish. This shrimp has been known to eat small fish without thinking twice.
Most shrimps are scavengers and don't necessarily need to be fed overtly (they usually eat food dropped by fish). If your fish your fish consume most of the food before it makes it to the bottom of the tank, then some extra food should be given to the shrimps after the fishes have been fed, or at night (most shrimps are nocturnal). Shrimps readily accept most frozen foods and dried foods (brine shrimp, flake food, etc.).
Stay away from Harlequin shrimps Hymenocera sp. as starfish are their only source of food.
There are many different type of crabs, but the most commonly seen varieties are anemone crabs Neopetrolisthes ohshimia, arrow crabs Stenorhynchus seticornis, and hermit crabs Dardanus megistos. Anemone crabs live in anemones, as do clownfish (e.g., Sebae), and vary greatly in color and shape. They are usually acquired indirectly by buying an anemone, but are some times sold separately. These crabs should have a host anemone to feel comfortable. Arrow crabs are very interesting animals which should be kept one to a tank, as they will continually fight. Also, Arrow crabs should not be kept with Coral Banded Shrimps as they will fight as well. Hermit crabs are also interesting, and vary in color and size. Most are passive, butsome will eat corals and other invertebrates.
Crabs are generally omnivorous and readily accept the same foods as your fish. Like shrimp, crabs can only eat food which has made it to the bottom of the tank. Thus, ensure some food is in reach of your crabs.
Most sea urchins and Starfishes are suitable for beginners who have a few months experience. Once again they vary greatly in size, shape, and color. Beware, some sea urchins are poisonous. Most sea urchins and starfish feed on detritus and algae, and small particles of food that have fallen within their reach.
Simply put, amemones should not be kept by beginners (sorry folks). They all require very strong lighting and excellent water conditions. Do not believe a fish store guy that tells you otherwise. Unless you are willing to invest a lot of money in proper lighting, do not try to keep an anemone.
Invertebrates are very sensitive to water quality. Signs of stress due to poor water quality will usually be exhibited first by invertebrates. Therefore, shrimps, anemones and other invertebrates should never be used to cycle a tank. Moreover, you should never add an invertebrate to a diseased tank or a tank which does not have stable water quality parameters (e.g., pH, temperature, etc.).
Other points to note. Shrimps need iodine to properly molt, as well as calcium . If you do not change water regularly (which you should), or if you do not feed live or frozen food frequently, then you may need to supplement your water with iodine. Without proper levels of iodine, shrimps will not molt properly and will most likely die. Also, copper kills invertebrates at much lower concentrations than fish. If you have ever used copper in your tank, DO NOT put invertebrates into the tank. You will never be able to adequately remove all the copper such that you can keep invertebrates alive and happy. Finally, crabs usually outgrow their shell sooner or later. Therefore, you will need to provide a new larger shell (they usually try a few out before sticking with one, so you will probably need at least a couple).
Tridacna clams (they need strong lighting), Flame scallops (they are nearly impossible to feed in an aquarium as they are filter feeders), Octopi (they have very short life spans), Nudibranchs (they are difficult/impossible to feed), any hard or soft coral (they need very strong lighting), and sea squirts (they can release poisonous toxins into the water).
Since saltwater fish are usually more expensive than freshwater fish, you have a great stake in getting them home alive and keeping them alive for the long term. You must realize that most fish you see in stores were swimming around the vast ocean a mere week ago. As such, the stress of capture and transportation can wreak havoc with the biological processes of the animal.
The most important thing when buying a fish is to not be overcome by the buying impulse. Before buying any animal, you should ask `Can I keep it happy'. Merely keeping the fish or invertebrate alive doesn't mean it is happy. Fifty goldfish may live in a 10 gallon tank, but they certainly won't be happy or healthy. Buying a fish you know nothing about and then asking if you can keep this fish happy is a very bad practice. Also, as hard as it is to say this, don't feel like you are doing a sick fish any favors by taking it home. If you have the room and time to nurture the sick fish, then I suggest you help out the environment and care for the sick fish rather than letting it die. However, if you are just going to place the fish into your main tank because you don't have the time or inclination to set a up a quarantine tank, then don't bother. It will only result in the death of the fish and the lightening of your wallet.
Once you decide on a particular fish, don't be afraid to ask the store to hold it for you. A good store will always hold a fish for you (don't patronize stores that won't!). Also, ask to see the fish eat. If the fish is healthy and eating, then it most likely is a good specimen. Finally, check the fish closely for spots, irregular patches, missing scales, and wounds. Torn fins will usually heal and are not much of a problem.
Once you get the fish home you should set the bag in the destination tank, thus allowing the temperature to equalize. After about a half hour or so, add a 1/4 cup of tank water to the bag. Repeat this process once every 15 minutes for an hour, removing any water if the bag gets too full. Any water you remove from the bag should be disposed of. It will most likely contain parasites and other bad things.
After you have the fish acclimated to your tank's water chemistry, there are a couple of things you can do. You can place the fish directly into the main tank and hope for the best, you can give the fish a freshwater dip and then place it into the tank, or you could place the fish into a quarantine tank.
The best scenario is to give the fish a freshwater dip and place it into a quarantine tank. Keep the fish in the quarantine tank for 2 weeks and watch for signs of disease. If the fish gets sick, you can medicate the quarantine tank without affecting the chemistry of the main tank. If you are going to quarantine the fish, you should acclimate the fish to the quarantine tank's chemistry, not the main tank.
If you don't use a quarantine tank, then it is a very good idea to give the fish a freshwater bath before placing it into your main tank. The freshwater bath will cause any parasites attached onto the fish to let go and remain in the freshwater (to die a lonely death). Otherwise, parasites left to their own will reproduce very rapidly in captivity and usually infect all the fish in the tank.
To give a marine fish a freshwater dip, prepare a container of dechlorinated freshwater with a similar chemistry of the destination tank. That is, make sure the pH and temperature are as close as possible to the destination tank (this is critical!) . Remove the fish from the bag and place the fish into the container for 3 to 5 minutes. Watch the fish closely for signs of stress. If the fish stops moving or begins to float, remove it immediately and place it in the destination tank (either the main or quarantine tank).
In placing the fish into the freshwater bath, never pour the fish into the container. Use a tupperware container or a net to capture the fish and place it into the dip. The store water should never be introduced to the freshwater bath, or any of your tanks. This water usually contains all sorts of nasty diseases and organisms.
If you put the fish into the main tank and it comes down with an illness, it should be removed to a quarantine tank immediately. Do not risk spreading the illness to the other fish in the tank (although it may already be too late).
Some more information on setting up a quarantine tank can be found in the Archives.
Succès à long terme
Débuter en eau de mer