Hospital Tank : This is definitely a must. It can serve three different tasks. A hospital tank, a breeding tank and a quarantine tank. It should be equipped with a sponge filter, a submersible heater, light and some gravel (not much). Glass tanks are highly recommended because they are not easily scratched.
Hospital tank : To be used whenever a fish is ill and needs special treatment. You can then isolate the fish and treat it alone instead of exposing your main tank to the side effects of the medication. This is also a way to save money. Fish medications cost very much and in order to achieve the right concentration in a 490 liter tank you will need 10 times more medication as compared to a modest 50 liter hospital tank. Remember to clean the tank every time the treatment is over. You must remove all water, clean it dry, clean the sponge with lots of water. This is called precaution measures. Every medication has some active or inactive metabolites which may remain in the sponge for months and be dissolved once water is added again, thus harming (even killing) the next fish which will enter your hospital aquarium. Water changes in hospital tanks must be preformed much more often than normal tanks because a biological filter is not present and all ammonia and fish waste, along with medication byproducts are still in the tank. I recommend at least two 50% changes every week. Another point is to feed carefully and never overfeed. In a hospital tank this may kill your fish much more effectively then the infection you are treating them for.
Breeding tank : Some prefer to use a separate tank for breeding or simply keeping their female mouthbrooding cichlids till the fry is big enough to survive alone. This tank should have some hiding places and gravel on the bottom.
Quarantine Tank : I could give you hundreds of first class quotations on this one. I will just give you our logo "Prevention is better than Treatment" as told by Hippocrates 2.500 years ago. I believe the modern equivalent is "a gram of prevention worth a ton of treatment". Whenever buying new fish please use the quarantine tank. You will save yourself a lot of troubles and your fish of many health problems. Never trust a fish which you have not been observing closely for at least two weeks, no matter how active it looks.
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Medications : Being a pharmacist myself, I was really astonished by the ignorance of both petshop owners and aquarists. Most medications required for the treatment of aquatic diseases are 10 times more expensive than the same (normal) drugs available for humans. This site will have served its purpose if you just understand this simple truth. All Health Systems try to keep the cost of human drugs down (for budget reasons of course) but none cares about your hobby and how much you spend on it. Therefore companies produce drugs for fish and other pets at 10 fold increased prices. Don't let them take advantage of you. Check your books or the internet, find what is the active substance you need and then go to your pharmacist and get the human equivalent. Since you are perhaps not a pharmacist yourself, be sure to get exactly the same active ingredient. For example, erythromycin stearate and erythromycin sulphate are not the same as erythromycin. The term "hydrochloride" next to an active ingredient means it is a salt, therefore soluble in water (hence it can be used for your fish) while the term alone (the base) is most often not. I have had excellent results in treating even cichlid bloating with drugs meant for human use (minocycline by Lederle for those interested).
Remember to check if the medication calls for removal of the active carbon from your filter (most of them require you to do so). Active carbon simply removes the medicine from the water as it does with all chemicals. Another point is the compatibility with tap water conditioners. Most of these preparations tend to chelate and inactivate most medications. Since you can't know which medications will be chelated it is safer not to add the conditioner. Most medications require heavy aeration while the treatment is going on. It is a good idea to aerate heavily even if the medication doesn't tell you to. Feeding your fish a compatible medicated food is an excellent idea.
Sometimes, no matter how hard you try, your fish doesn't seem to respond to normal medication levels. If the problem is not life threatening you should just wait or repeat the therapy. However, if the problem is serious you do not have that luxury. In such a case you should simply overdose. I have had success with metronidazole added at 10 times the dosage recommended. The recommended dosage usually supposes that your fish will accept some food and that most organs function at some degree. In severe situations this is not the case. In order to cure your fish, the medication must reach the affected organ (e.g. kidney) at the correct concentration, which may require 10 times more medication in the water. For external infections, usually the recommended dosage is sufficient. Under-dosing and premature discontinuation of the medicine may lead to resistant strains of microorganisms which will prove lethal next time (the same medication ~ and all similar medications ~ will not harm these strains).
More related articles : Diseases in the aquarium , A disease list in alphabetical order (A-C) (C-F) (G-I) (I-N) (N-S) (S-Y), Diseases in the Aquarium - List of Active Ingredients in alphabetical order (A-S) (T-V), Over-dosing is better than under-dosing , When the going gets tough... , Sedation - Anesthesia - Euthanasia , Only you can save your fish , List of medication products by leading manufacturers , Activated Carbon , A "true" quarantine tank , A case of Pseudotropheus demasoni inexplicable deaths
Fish load : General rule of thumb : Three cm of fish length per 4 liters of water. If rocks and other decorations are added, you have to apply this rule for the actual water volume. This rule applies to fish up to 4 cm in length. Bigger fish require much more volume per cm of body length (you should count 1 cm of fish per 3 liters for fishes bigger than 20 cm). This calculation is for community fish only. Territorial and aggressive fish require disproportional high volumes per cm of body length. A 500 liter aquarium can't house more than 15 Melanochromis though the fish is relatively small. It can't even house two males !
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Gravel & Rocks. Wash them before adding them in your tank to remove dust. If you collect the rocks yourself, make sure metals are not leaking (by placing them in a bucket of water and measuring GH and pH or by dropping some vinegar on the rocks and see if any bubbles are formed), let them for 2 days in strong household chlorine solution, wash them till you no longer smell chlorine, add dechlorinator (water conditioner) in the last washing and let them dry. If making rockscapes, you should glue rocks together with aquarium silicon to avoid collapsing of the formation. Let the silicon dry very well before adding the rockwork in your tank - allow at least 72 hours.
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