So, I've been reading about the stress signs of discus; what kind of darkness does a discus show if I'll or stressed? Like darker colour of it's original colour or a blacken?

I learned Saturday that blackened fins means the fish is not doing well.

Blackened discus= big trouble. It looks like is a disease caused by a virus which weaken the imune system. The fish will fight against the virus but must be helped against secondary bacterial infections with antibiotics. If that's your case you may lost some fish. Later I'll describe my experience with that disease. You can find pictures online with discus afected by this disease.

We were at Sierra in Renton Saturday and their Discus tank had like 4 of them that were dying and all their fins were black and the fish were basically slumped on the gravel against the glass and ornaments. They looked sad.

Wow.
Now that is bad. I was worried my new discus are too stressed, but it ain't anywhere near that kind of suffering.

The fish which survive to this disease gets imunity but can spread the virus.
Last december I had 6 happy discus in my 75 gal tank and I bought 2 other from a local breeder(because bobby is so much involved on this forum I have too mention that IS NOT BOBBY). The fish were absoluty gorgeous but it looks like they spread the virus in my tank. After 2-3 days all the other discus start to blacken, the 2 new discus were OK. I start to treat all tank with Eritromicin, half dose because I had Cardinal Tetra in that tank. I've lost 3 discus but I saved other 3. The 2 new discus were unafected by the virus.
I can't say nothing about the fish at Sierra because I didn't see them, but anybody can have their own conclusions.
Looking forward to hear more opinions from the discus people on this forum.
Late edit after saw protcl's posting: Protcl please don't jump to any conclusion before positevely identify your fish problem. They maybe only stressed...Compare your fish with the pictures available online.

balck fins are fine..... black stripes fine..... you just gotta worry that they are too stressed if they completly turn very very dark... all the body.

Really, Sand, cuz all the dying ones at Sierra (and there were quite a few) had black fins. The healthy ones were normal.

A picture worth a thousand of words. If you see a sick discus(blacken) you will have no doubt.

spyral - its called "dirty" or "peppering" when they have black spots on the body or dark fins.... actually these fish are allot easier to breed cause they dont have a problem secreting that mucus food for there young... the really clean discus are usually your grade A pigeon, or marboro.... and they typically cant raise there own fry but you have to have suiter parents for there young.

Every one of my discus have dark fins.... not willing to pay 80+ dollars for grade A clean fish that will give me trouble with breeding later.

so the blackened ones laying on the bottom were just sleeping?

lol.... if there body was blackened, Im assuming they were near death.... if it was just there fins that were dark, then most likely sleeping? lol

Well, my discuses are not blacken in any way, I guess still not comfortable yet.
There was a cucumber floating around, I grabbe it with my 20" tweezers and then all 3 if them formed a defensive barrier!!!
Kinda funny and interesting.

Oh well...

Hey sandnuka: what do you feed your discuses?

they are currently on a frozen bloodworm only diet.... to kinda get the spawning.... they love em.

How long did it take them to get comfortable?
Mine still tries to avoid me.

probably a month or longer of hand feeding (well hand in the tank with bloodworms) but they didnt start comin to my hand until itleast a month or so..... they are a really skittish fish, the more you just sit in front of the tank and watch them... the faster they get used to you... if you have to net one, or move around decor in the tank, starts all over.

we need to see some pictures!

just saw one the discus laying on its side...too sleep?
i thought it was dead!, until i tried to net it and then BAM!, across the tank it went.

weird.