Health of Your Discus:

FIN & BODY ROT
Fin & body rot normally are caused by either bad water or a sudden change in environment.

1. Water has a high biological content rotten food and detritus this causes a high bacteria count
2. Sudden temperature change will give them a cold then there immune system drops
3. A large water change with water not in the same parameters as the aquarium such as pH or hardness will cause osmosis damage to the fishes skin like a scald this allows the bacteria to enter you will often see if you do this or by a fish from a shop and you don’t acclimate it slowly the tips of the fins will go milky.

If you maintain your aquarium with regular small water changes and acclimate the fish correctly and invest in a UV sterilizer you will probably never have to deal with this.

Once you have this it can be highly contagious due to the makeup of a discus its whole body is a food source for its fry so if one fish is covered in bacteria and rubs or touches another that fish will be likely to contract the bacteria.

Also health fish often pick on sick fish and in doing this the healthy fish contract it.

I have found the best way to treat this is to do daily small water changes. And use either an antibiotic like Metronidazole i have also found melafix and pimafix mixed 50/50 works well if done early.

WORMS: 
Almost all fish should be wormed at least once every three months, everyone worms their dogs, cats, and birds but not their fish? Many fish of all types die prematurely from worm infestation. Most worming medications in my opinion should not be placed in the aquarium water, but rather mixed with the food. This can be done with pellets or meaty foods. Praziquantel is available at aquarium shops or vetrenarian and is excellent for tape worm control. Crush half a tablet to powder and mix with beef heart and feed. Make enough for three days, (store in fridge) one feed each day, can’t get any easier than that. Fenbenbazole (panacur) is another good medication used mainly for round worm. Panacur should never be used poured directly into aquarium water or you will probably kill all of your fish, but mixed with food it is very safe. Simply place some pellets in a small container and sprinkle with panacur and feed. Feed once a day for three days. Panacur is available from grain and produce stores, sold as a sheep/cattle/goat wormer. Metronidazole can be obtained from a vetrenarian and is widely used as a preventative against Spironucleus and Hexamita, use in the same manner as Praziquantel.