Slight Concern

I bought 6 cardinal tetras last Friday at the lfs. They looked pretty good but when I got them home I notice one of them has a white upper lip.... It isn't fuzzy or anything so I was just wondering if it was possibly a wound. Here's the best photo I could get.....



I am pretty concerned that it will spread to my other fish if it is a disease. So far everyone is acting normal. I don't know if this is paranoia or if the rainbows have always looked like this but heres a photo of one of my rainbows mouth:



The light is hitting the rainbows mouth making it look lighter in this photo. To be honest they don't look any lighter than photos I've seen on the internet but I'm paranoid as I don't wanna lose them. Yikes...I hope this isn't bad news as I'm pretty sure with plants my medication options are limited.

Water parameters I'm not sure on but I've been doing one 25% and one 50% water change a week minimum. It was even more frequent when I first set up the tank a while back.

Nervous.

I have had the same thing on some of my fish, the rainbows and pearl danios especially. It had me worried too as I did not know what it was. Still don't, but it didn't seem to bother the fish or turn into anything more that the spot on the lip. Maybe they were swimming to fast and not watching where they were going.  Anyway, maybe someone else has more information.

Rainbows often get the white mouth/lip from crashing into the glass. I love my 'bows, but I am really glad they don't get to vote.

That tetra in the first picture (not a cardinal) looks like it could be a fast Astyanax type - if not, it's another open water shoaler because of its silver sides. They respond to stress by running, and they run into glass at the store. They figure out the general concept way more quickly than a rainbow does, but it does look like that sort of injury - the fish version of a really fat lip.
It can take a very long time to heal, but it isn't usually something that develops into a full blown infection.

Yes, I was going to mention that it did not look like a cardinal .... looks to me like a Columbian tetra.

GaryE wrote:Rainbows often get the white mouth/lip from crashing into the glass. I love my 'bows, but I am really glad they don't get to vote.

That tetra in the first picture (not a cardinal) looks like it could be a fast Astyanax type - if not, it's another open water shoaler because of its silver sides. They respond to stress by running, and they run into glass at the store. They figure out the general concept way more quickly than a rainbow does, but it does look like that sort of injury - the fish version of a really fat lip.
It can take a very long time to heal, but it isn't usually something that develops into a full blown infection.

Hahaha, well I'd rather they're daft than diseased...... I experienced a bad bout of columnaris in a tank when I was younger and would prefer not to come across it again... I figured they were ok and it was just an injury because it wasn't fuzzy looking at all and everyone is acting normal. I'm not surprised they've inherited some wounds as there was about 15 of them in 8 gallons of water... They're pretty fast and like to chase each other from time to time.

Also:

Oh my....   I must have cardinals on the mind because I saw some very nice looking ones at the LFS recently and wouldn't mind acquiring them as well! How embarrassing as I know these are columbians and have been looking for them for a while, I was even going to try to special order them! They are very nice shoalers indeed.

Cardinals are slow little things - you'd have to shoot them from an airgun (don''t!) for them to get the white lip thing.
I wouldn't keep them with Colombian tetras. I like that fish, but it is too nasty for a cardinal. It is really likely to bully the smaller fish.

Agreed.... I keep my Columbians with mid-sized cichlids like firemouths.....

So far, they aren't picking on my rummynose tetras and I hope they don't as I'd like a larger shoal of rummys, likely 12 (5 more). They seem more concerned with eachother...