eye's of discus.

[1077]

I have one dominate discus out of a group of four and for the most part they get along with the exception of feeding time. The dominate males pupils in it's eyes becomes vey small at this time and i have not observrd the same with respect to the others. I am wondering if anyone else has observed similar characteristic with their fish. At all other times it's pupils appear larger. At feeding time the eyes also appear to be a much brighter red almost orange than at other times. The fish in question is a healthy fish with no indication of illness it is just something i have observed for sometime and was curious about. thanks in advance for any and all responses.:) Please forgive me for calling this fish a male. It is sometimes hard not to associate It;s actions with male behaivor exhibited with other species.

[brewmaster15]

HI,
Its not uncommon for a discus to flush its eye's Iris with blood when angry or excited...often the eyes of red fish become even more red in appearence.. (happens in Brown Iris fish as well...the red effect is hidden more..). The Iris of your "male" fish may be "looking larger"
as it gets flushed with blood. I say looking because the iris of a fish doesn't move like ours do...It stays rigid regardless of the amount of light on it... as I understand it. That means the eyes pupil can't get bigger or smaller, just the impression of it happening by blood flow and pigment manipulations.. Also what may happen is the lens may move forward or back...changing the amount of light you see reflected and again the impression of pupil size change... ( in Human, our lens itself changes shape...fish lens don't..they move forward and to the back of the eye.)

hth,
al

[1077]

Thank You for response and information it is helpful.

[dixiedog]

1077, do you mind if I take your question a step further?

With the characteristic red eye of the discus being a desirable trait, I was wondering if this was a product of heredity, or of environment. In other words, would this guy (or gal?) have a redder eye if I fed him differently, or adjusted his environment in some way?



http://i33.tinypic.com/10epxf8.jpg

[prolude006]

Well my Cobalt discus has a very red eye all the time. My blue diamond's eye is completely dark. My red turquoise's eye was red until it spawned with my cobalt and now its very dark(black) and has not changed back since.
so i am curious as well.:confused: