Discus with white or clear poop and not eating

Problem

1. Please explain the problems with your fish. When did you notice the problems and did anything unusual happen that you think started them?
I have problem with 2 discus 4.5 Inches. Both not eating and I saw one of them has white clear poop (noticed 2-3 days ago) and another I saw nothing ( more then one week).

2. Symptoms (i.e. turning dark, excess slime, not eating, clamped fins, flashing, darting, clamped gills, white/yellow/green poop, hiding, headstanding or tailstanding, white on tips of fins, rotting or fungus, blisters/white zits on fish, bloated, cloudy eyes, wounds).
Not eating and white clear poop. Tails standing sometimes on the bottom.

3. What medications/ treatments have you already tried and what were the results. Include dosage and duration of treatment.
I used Esha hexamita without improvement. They are now in quarantine tank with Epsom salt and anti internal bacteria from Interpet.

Tank/Water

4. Tank size and ages, numbers and sizes of fish.

Main tan tak is 6x2x2
Cca 30 discus from 3 Inches to 4.5Inches

5. Water change regime (What percentage and how often).
50-60% per week.

6. How long has tank been running? Is it bare bottom? If you have substrate, what type and how deep is it?
1 year

7. Do you age your water? If you do for how long and what is the ph swing.
I don't understand question. I using tap water only.

8. What type/brand water conditioner do you use? Do you add it to the tank or aging barrel? How much do you use?
Seachem prime

9. Parameters and water source;

Note: Water Parameters are important in diagnosing problems within a tank. If you don't own test kits for the following information, you can purchase them, test your parameters and post this info as soon as possible.

- temp __29 celsius___

- ph _7.4____

- ammonia reading 0____

- nitrite reading 0____

- nitrate reading __40ppm__

What type of water or combinations of water sources do you use? If it is an RO/tap/well water mix, please list percentages in the mix.

Just tap water
- well water ____

- municipal water ____

- RO water ____

10. Any new fish, plants or inverts added recently.

No

11. Please tell us what you feed your fish and how often. This can be critical information for solving the problem so be as specific as you can.
U use salmon and cod mix, spinach, garlic, spirulina, Astaxanthin, Spirulina. feed them`5-6 times a day

12. Include any pictures or videos you have which shows the symptoms. If you can't add them to this post, please provide a link to them.
https://www.youtube.com/watch?v=IsBSSciwj9Y