Heeeeelp!!!!! my betta is sick!!

[andreig09]

for two days ago i notice that my betta is behaving strangely, he stays at the bottom of the aquarium and he don't swim like before, today, i was watching the tank and i notice that he has a a bump behind his left gill... ¿what can i do?

attached sheet and some pictures:

1. What is the size of your tank?
6.6 gallon
2. What are your water parameters? State the brand of test kit used.
temp: 26º, ph:7, no2: 0,1, no3:0
3. Is your aquarium set up freshwater or brackish water?
freshwater
4. How long the aquarium has been set up?
2 months
5. What fish do you have? How many are in your tank? How big are they? How long have you had them?
1 male bettafish, i have it for 3 months, before being transsfered to this tank he lives in a smaller tank
6. Were the fish placed under quarantine period (minus the first batch from the point wherein the tank is ready to accommodate the inhabitants)?
yes
7. What temperature is the tank water currently?
26
8. Are there live plants in the aquarium?
yes, vallisneria, cabomba, lemna minor and acorus gramineus
9. What filter are you using? State brand, maintenance routine and power capacity.
a bag filter
10. Any other equipment used (aside from heater and filter which are two very important components of the tank)?
no
11. Does your aquarium receive natural sunlight at any given part of the day? What is your lighting schedule (assuming you do not rely on sunlight for our viewing pleasure)?
yes it recieves, but not directly
12. When did you perform your last water change and how much water was changed? How often do you change your water? Do you vacuum the substrate?
last week, 1/3 of the water, i change the water once a week and i vacuum the subrstrate
13. What foods do you provide your fish? What is the feeding schedule?
once a week i give him bloodworms and the other days pellets
14. What unusual signs have you observed in your fish?
he stays at the bottom, don´t swimm very much and he has a bump behind his gill
15. Have you treated your fish ahead of diagnosis? If so, what treatments did you use? State your reasons for planning ahead of proper diagnosis.
no

[BakaMandy]

Hmmm :S

Is the temperature in F or C btw :P? I'm assuming C though, lol

Anyway, does he show any other signs? like rapid breathing? Does he eat? Because I'm guessing it is either tumor or internal parasite.

However, tumors don't usually effect a betta's daily life, but because it's at such close proximity with his gills, it might have had some effect on his ability to breath, therefore effecting his regular activity. Tumors are common in betta fish so I wouldn't be surprised if it were this )':

My second guess was parasites because sometimes internal parasites live under a fish's skin, producing a bump. It often causes listlessness, and the betta will also become thinner even though it might still be eating (hense why I asked if he was still eating).

I asked if he appeared to be rapidly breathing cause it might be a sign he's having trouble breathing.

In any case, I'd recommend transferring him to a smaller hospital tank for closer observation. Treat him with a bit of aquarium salt (1tsp per gallon) and perhaps even a bit of Epsom salt (1/8tsp per gallon. if it's a tumor, the salt will help reduce the swelling a bit.) I don't know about using medicine right away though, maybe keep an eye on him to see if the situation changes