Cotton mouth or something else? (RainbowFish)

Around 3 of my rainbow fish have this bizarre white appearance on their lips. It doesn't look fuzzy like cotton, just a little lumpy. I began treating the tank with pimafix for 6 days, but it doesn't seem to be going away.

Is this cotton mouth, or did they cut their lips on something? I've added a few pictures below.

(Also, the rest of the fish in the tank are fine and the parameters are good the last time I checked)

 

Happy to share my experiences and will also recommend doing a search on this site for “rainbowfish mouth/lips“ etc.

rainbowfish in general seem to be prone to these types of issues. They have very sensitive mouths (at least some species) I also keep Boesemani among others and they seem to be the worst - most sensitive. Seems to happen after vigorous swimming either chasing rivals/females or spazzing during water changes - they bump into objects In the tank - white lips. Sometimes a little stringing mostly just swollen looking. happenned way more in the beginning than it does now as they are older and calmer. Also on the advice of others I stepped up my water changes and reduced nitrites as low as I could that seemed to help be “preventive“ it still happens ,but goes away on its own in a couple days. If it sticks around then it’s likely something else - I’ve treated for lip fungus in another tank when an Australian rainbow had a white nose for a week. I treated with primifix for a few days and it’s gone as is a small patch on the side of a different Australian.

few Questions - how long have you had them ?

Have they recently reached maturity ?
(they go crazy trying to breed/chase etc)

Behavior changes (hiding twitching etc) ? Eating good ?

Stress in the tank? Any aggressive new friends ?

Just things I’d be looking out for in combo with the mouth. If it continues persists and/or they have other symptoms/behaviors changes I’d recommend the emergency template and others can add in additional thoughts for sure.

most people may be reluctant to blind guess and the template gets to the details.

GL feel free to ask any questions I’m no expert but have been keeping rainbowfish since I started and have learned some.

 

Happy to share my experiences and will also recommend doing a search on this site for “rainbowfish mouth/lips“ etc.

rainbowfish in general seem to be prone to these types of issues. They have very sensitive mouths (at least some species) I also keep Boesemani among others and they seem to be the worst - most sensitive. Seems to happen after vigorous swimming either chasing rivals/females or spazzing during water changes - they bump into objects In the tank - white lips. Sometimes a little stringing mostly just swollen looking. happenned way more in the beginning than it does now as they are older and calmer. Also on the advice of others I stepped up my water changes and reduced nitrites as low as I could that seemed to help be “preventive“ it still happens ,but goes away on its own in a couple days. If it sticks around then it’s likely something else - I’ve treated for lip fungus in another tank when an Australian rainbow had a white nose for a week. I treated with primifix for a few days and it’s gone as is a small patch on the side of a different Australian.

few Questions - how long have you had them ?

Have they recently reached maturity ?
(they go crazy trying to breed/chase etc)

Behavior changes (hiding twitching etc) ? Eating good ?

Stress in the tank? Any aggressive new friends ?

Just things I’d be looking out for in combo with the mouth. If it continues persists and/or they have other symptoms/behaviors changes I’d recommend the emergency template and others can add in additional thoughts for sure.

most people may be reluctant to blind guess and the template gets to the details.

GL feel free to ask any questions I’m no expert but have been keeping rainbowfish since I started and have learned some.

Thank you so much for the detailed reply! I didn't know this was a common thing amongst rainbow fish. To answer your questions:

how long have you had them ?
Not long, maybe around 3 weeks.

Have they recently reached maturity ?
(they go crazy trying to breed/chase etc)
the males are chasing the females, so I believe so.

Behavior changes (hiding twitching etc) ? Eating good ?
The rainbows become piranhas when I feed them, and they seem to be acting normal.

Stress in the tank? Any aggressive new friends ?
The only aggressive fish are the angelfish, but they only occasionally nip at the rainbows.

 

So being new they are bound to bump into stuff, and when they chase the gals, and again if the Angel looks sideways and they run. Any of these could make a fish bump into stuff. Rainbows seem to be prone to potential secondary infection. Keep a close eye, and let the heal and get used to the tank. I recently moved some pearl danios who must have thought i was delivering them to a torture chamber. They slammed themselves so hard on the rocks of the new tank several have scrapes now. Tank is established so I won’t worry to much unless other symptoms. I’d say your in a similar spot. Give it a few more see how they behave and then use template as needed To solicit more advice here

 

Just thought I'd chime in even though New2fishlovinit has already given you some great advice.

I have kuhlis; who also seem to be prone to injuring themselves easily. I've had a loach who started with a white bump on his mouth, which quickly spread and turned into a fungus. Figured it was from slamming into new decor. Applying methylene blue directly to his mouth/barbels was incredibly helpful; he bounced back quickly and the fungus went away. Along with this I was also doing large daily water changes.

Just an idea if anything progresses.