Is this bad?

[angel]

Yes that's bad test your water for parameters--all of them but ammonia in particular--and then do a water change stat!

[angel]

Angels do well with water on the softer side. That's fine. Ammonia was the first thing to rule out. Now look at some of the things that affect angels and cause redness. Hexamita and Septicemia are two. I can't remember which is which but one is caused by bacteria and one by too sterile of wat4er conditions . I'm not sure about the CO2, I've questioned fish and CO2 together because it doesn't make sense to me how it works . But it's something to look into. Gills that red and more than a thin red line at the fins are not a good sign and angels are easy to lose so do some checking on those two conditions and hopefully river11 and sirknight will be looking in shortly and can lend some solid advice. And JD. But the first thing is always water change and don't be afraid to do 50 even 80 percent. Of course and make sure there's no chlorine.

[angel]

With blushing angels yes they should "blush." Only at their gills, of course. I lost many angels to something that got introduced into the tank and ran rampant and the only way I found out there was something with the redness was I got some fish from river11 and they were so light I could see the red at the fins. It was just like that. Also there was red at their mouths. With the darker ones I couldn't see the red but it would have been present. I treated with clout and mega water changes. It cleared up in days and they've been fine since--no redness.

[angel]

The differences are I didn't have the red gills like that, but then mine weren't blushing. And yours don't seem to have any red around their mouth area.
I had thought river11 did only blues. It never occurred to me they would be blushings.

[angel]

Angels are far from easy. You'd think they'd be a breeze as many of them as there are in the pet stores. It's the keeping them alive that's the difficult part! Noticing something wrong and taking action on it right away is how we handle that, and only learn it by listening to the longterm angelkeepers about husbandry and signs of illness. You used your instincts and turned off the CO2 and if that cures what was wrong, it means you ARE a better fish keeper!