I hope I wasn't too lengthy with my post. Here is a concise version based on the questionnaire if that helps. I do feel like I answered all the questions in the above post, but it can be good to have it all in one spot. I unfortunately do not have a decent camera at this time, but I will see if I can get a hold of something to post photos after work today.
1 and 2. Two juvenile Discus are not accepting food. One is on its 13th day without eating, and hasn't accepted food since being entered into our tank. It looks thin and weak. The other is on its third day, and first accepted food and then stopped accepting food. They hide in the corners of the tank or in a hollow rock ornament most of the time. They sometimes lay diagonally against the sand but not completely sideways. Typically they would lean against the base of a plant or ornament. They are pestered by another juvenile that is a bully, but sometimes they do get along. There is a larger Discus in the tank but it is not aggressive toward the juveniles. It occasionally has a clear string substance seen attached to its lower fins and may be malnourished. All my Dsicus occasionally rub against the plants and driftwood as if scratching an itch, but not excessively. We haven't changed anything specifically except for adding more Discus to help make them happy.
3. I haven't tried anything yet. I am worried about potential risks of dosing fish with an antibiotic. Anyone's experiences would be helpful. I did purchase API General Cure which has 250mg Metronidazole and 75mg Praziquantel.
4. 60 gallon, four juveniles in the 2"-2.5" range and one 4.5" Discus. 3 small bottom feeders and a couple tetras and guppies are also in the tank.
5. We change 40-60% of water and siphon tank 4-5 days a week.
6. Approximately a month. Thin layer of sand substrate. Approximately 1/4"-1/2".
7. No aging of water occurs. We treat our tap water with API Stress Coat+, Live Nitrifying bacteria, Black Water for softness, and API Leaf Zone for our plants. pH never changes. Consistently 7.4.
8. Temp is 84 degrees Fahrenheit. Test results from this morning. Nitrate is 5-10 ppm. Nitrite is 0.5 ppm. Ammonia is zero. chlorine is zero. Treated tap water is used.
9. Only addition is more Discus. We have a lot of plants in our tank though.
10. We started feeding live black worm to try and get our fish to eat. They are now hooked and won't take other food. Feeding is a few fingerfuls of black worms 3-4 times daily.
11. I will try to post images later this evening if I can get a camera. Thanks!