Good day

Yesterday my oscar developed a pink pointy lump under his lower lip, with swelling inside his mouth, it is about the size of an eraser at the back of a pencil, a few minutes ago my wife said that it is the same size as yesterday, and he is not eating.

he is 30+ cm in size,

Any help please, I will take a photo tonight and post it.

Regards

Oscars often have what looks like a pimple on the end of their lower jaw. I have seen Oscars with quite large protrusions on the jaw. How long did it take to appear? What are your water readings, ammonia, nitrite, nitrate and pH? These are quite important factors to know, especially as you say your fish has stopped eating

Just in addition to what Penn said/asked: I found the pic again meanwhile on this website showing the normal lump Oscars often get; the one in the pic is quite small, they can look bigger and pinkish. It's here . Hope that works now.

The lump appeared suddenly yesterday, well took a few hours, when I checked the water last weekend all the readings were good, I'm going home now to check the water. the lump is much bigger than your picture

Thanks so far, I'll be back

does the lump look like its infected in any way or does it just look like a growth/pimple,ive its a growth type lump then u shouldnt worry bout it as oscars get these growths due to the bottom jaw shuffling gravel,sand ect.keep a eye on yr oscar try and get him to eat.

If the point is on the outside of the front of the bottom lip and it is a pimple size then its normal, but if it is bigger and on the inside it sounds like a problem. We need the exact readings for ammonia, nitrite and nitrate. Its sounds like a swelling from your description of its size. Its not in a place that is common but i am gonna guess its a bacterial infection.

What other fish have you with your oscar and has there been any fighting recently. Some fish with smaller mouths than oscars bite the lip when they front up an oscar

I'm back, was away yesterday, He's eating, I had a close look at this thing, it is a big pimple like thing, he does like to shovel the 3mm gravel, I think he's trying to tunnel out of the tank, the reading on Wednesday was, Nitrate 25, nitrite 0, GH 6%, KH <3%, PH 6.4, I don't have an ammonia test, but I believe that the NO3 and NO2 indicates total ammonia (Yes/No) I did take picture, but then had a few beers and forgot to download themB)

Its good he is eating. If its a pimple then it is perfectly normal and very common. Have a look for some old threads, this is a common worry and has been mentioned many times

Nitrate and nitrite dont equal total ammonia. Your fish produce ammonia (all animals do, its what make your urine smell). In an established filter bacteria feed on this and produce nitrite. Other bacteria feed on this nitrite and produce nitrate. You reduce nitrates by doing water changes. Ammonia and nitrite are poisonous to oscars, nitrates less so. At low levels nitrate is ok to oscars, at high levels it will cause problems. A nitrate reading of less than 20 is ideal, 40 or less acceptable


So in an established tank the bacteria in the filter will be in balance with the amount of fish you have so you will have a reading of ammonia and nitrite of 0