Discus not eating and Color issue

[sychase]

Hi guys!

I'm a newbie from the Philippines, I bought 8 discus last week and after 2days I noticed 1 of them barely eats(just saw him eat once or 2x with 1 pellet), he always isolates himself from the rest. No signs of heavy breathing,white poop or issues with him beside of being less active than the others. Whenever I approach the tank all the fishes are excited and swims towards the surface while he stays at the bottom of the tank.

He's also kinda aggressive towards other fish whenever they get near him. He's also one of the biggest(at 4") so I also don't think he gets bullied...

I only feed them with sinking pellets from Japan. Is it possible he doesn't like the food? it's been more than a week.

This is him.
http://s32.postimg.org/iotl9w0n5/IMG_20160512_140438.jpg (http://postimg.org/image/iotl9w0n5/)

Another Picture of him(the fish at the back
http://s32.postimg.org/f9yjr9yyp/IMG_20160511_081555.jpg (http://postimg.org/image/f9yjr9yyp/)

Also will their colors improve? or Do I need to feed them something to improve color?
Cause I was hoping them to be a solid red/orange color (Super red melon)


Water Parameters:
Temp: 83F or 29C
Ammonia: 0ppm
Nitrite: 2-5ppm
Nitrate: 5ppm
Tank Size: 75gal
Feeds: Sinking Pellets only
Discus size: 3"-4"
I water change 30% daily with Tap water and StressCoat+ and Quick start.

Thanks in advance!

[Filip]

How many gallons for 8 discus ?
What's the filtration and is the filter cycled?
Having Nitrites tells me that your tank is not properly cycled yet. You can't allow nitrites with discus.
How many times you feed daily?
30% wcs a day is too little for juvies. you should consider doing at least 50% a day.

Yes they will get more beautiful and red as they grow.
Feeding salmon, astaxantine pellets and other foods enchances their red colouring.
HTH.
BtW, nice discus and good luck.

[Ata.Sultani]

you can check out my post also same problem here with same discus as you get red marlboro discus with photos look what i done step by step..... and tell me how you measure nitrate , pH level of water etc, etc, of your tank is there any instrument you get ? my post as in given link

http://forum.simplydiscus.com/showthread.php?124484-Red-Marlboro-Discus-is-Not-Eating

[Ata.Sultani]

you can check out my post also same problem here with same discus as you get red marlboro discus with photos look what i done step by step..... and tell me how you measure nitrate , pH level of water etc, etc, of your tank is there any instrument you get ? my post as in given link

http://forum.simplydiscus.com/showthread.php?124484-Red-Marlboro-Discus-is-Not-Eating

[MendoMan]

With that high of nitrites i'd suggest changing at least 80% of the water at least once a day until your tank cycles.