The 3 things i add after EVERY water change are: Koizyme -Keeps bacteria at bay. Prevents Redleg, a disease that kill your frog once they get it. Just add 1 drop to your tank with an eye dropper.  Keep the Koizyme in the fridge. and shake it before using.   Buy It @ www.xenopus.com Aquarium salt - Keeps fungus in check. I add 1 tbsp to the tank. Stress Coat - This is a water conditioner that removes chlorine and metals from your tap water. It also helps replace the natural slime coating that your frog has to protect it from bacteria.  I add a good tbsp to the tank. Meds that i have on hand in case of illness: Melafix - An antibacterial medicine. It repairs open body wounds, mouth fungus, etc. Pimafix - An antifungal medicine. Treats fungal infections. Also treats internal and external bacterial infections. Ick Away - A medicine for Ick, which is a parasite. The active ingredient is 0.075% malachite green in an aqueous solution. Signs that a frog may be ill: -refusing to eat -hanging at the surface of the water -not as active -rash -pale color -redness/inflammation If you think your frog is sick, remove him to a separate quarantine tank asap. Then do a water change in the tank he came from. Keep a close eye on the other frogs to see if they change their behavior or eating habits. After the frog is in his hospital tank. I would add 1 & 1/2 tbsp of aquarium salt, 1 + tbsp stress coat, and the medicine if you can diagnose the illness. Diagnosing a problem: Skin Shedding - Frogs will shed their skin every few weeks. This is normal. Sometimes they will even eat it, this is ok. If your frog seems to be shedding excessively, he may have skin parasites. Injury - Though these frogs do not have teeth, they can bite one another. They can also scratch another frog with their claws. Usually a scratch will  heal up with 3 days,  I throw some extra salt in the tank as a precaution against infection. Exposure - Do not use any kind of chemicals in the tank. Be careful of the sponges you buy that contain an antimicrobial. Don't use them! I would just use plain old white (no prints) paper towels. I like the 'Viva' brand because it does not tear easily. Do not use sprays around the tank, or incense. These can pollute the water. Remember the frogs skin is permeable, they absorb everything through their skin. Do not use anything metal to hold a frog. Metal ions are toxic to frogs, it will kill them. Be careful of the water temp, too hot or too cold can kill your frog also. Bacteria- A main cause of death in frogs. Signs are swollen, and red skin. Eye sores,ulcers,twitching. Remember the water quality, it's very important to their health. Use the Koizyme.  Buy it at www.xenopus.com. Fungus - Signs are white strands with red inflammation. Aquarium salt helps tremendously with fungus. While the salt is not a medicine, it is a great preventative.  You could also use a 2% malachite green solution, and immerse frog for 5 minutes; do again 24 hours later. Nematodes - Tiny roundworms. In over-crowding, they are highly contagious. The skin on the thighs may start flaking and be gray. Your frog may lose weight. Bloated frog - Freeze-dried blood worms, among other worms, have been known to cause sudden (acute) bloat in frogs. Sometimes this might be mistaken for 'Dropsy', a disease which will kill your frog. The frog becomes so bloated with Dropsy, they look as if they may explode. It can be contagious. This disease is probably caused by bacteria. Separate the frogs, and treat with aquarium salt, 2tbsp:10gallons of water. I do not have all the answers here for treatment. Also refer to the "Links' for other sites that contain more care information. *IF YOU NEED TO LOCATE A HERP VET, CLICK ON LINK BELOW*