Silver Dollars problem

[Kronos26]

HI
I have just noticed that on 2 of my Silver Dollars that they have a reddish tint on there jaws and it goes up to the gills and not further and it is hard to see I had to look closely. Is this a problem or is this normal?

Can some one Help me please I don't want to loose them I have had them since they were small.

 

[buddha1200]

normal all my silver dollars have a red tint on their faces and lower belly

 

[Kronos26]

normal all my silver dollars have a red tint on their faces and lower belly

Thank you
that makes me feel much better
but why do the other 2 not have it? is it like 2 different types of silver dollars?

 

[Kronos26]

How big can a silver dollar get if fed correctly and in a suitable tank that is clean and healthy?

what is a suitable tank size for 4 silver dollars ( 1x 22cm, 1x 18cm and 2 10cm)

 

[Knowdafish]

How big can a silver dollar get if fed correctly and in a suitable tank that is clean and healthy?

what is a suitable tank size for 4 silver dollars ( 1x 22cm, 1x 18cm and 2 10cm)

http://freshaquarium.about.com/cs/generalinfo/l/aa112398.htm

 

[Kronos26]

http://freshaquarium.about.com/cs/generalinfo/l/aa112398.htm

Thanks but I think that the size they have there is incorrect because 2 of mine are over 5" mine are +/- 7" up.

I will try to post a pick of them