Okay, so I am a new Betta owner, and just by browsing the forums, I've already found that I've made three mistakes:
One, he's in a 0.5 gallon tank, two, there is no filter in said tank, and three, he has no heater.
His purchase was spur of the moment, and we were going by what the pet shop said was adequate for him.
Anyways, I did a complete water change for him on Saturday (with gravel cleaning) after giving him 1/4 a tsp. of Bettafix for a week (The bottle recommends a 1/2 tsp. for every gallon of water in the tank, and then to make a water change after a week. It never said how much of a water change). I gave him the Bettafix as a "just in case" precaution if he had anything from the pet shop (it was a bit run down).
So after the water change and placing the two fake plants back in the tank, he went into some sort of fishy fetal position and kept all his fins clamped together. I figured he was just freaked out by the whole ordeal and he returned to normal not long after.
This is what I'm worried about though.
He's taken up a habit of parking himself in some part of the tank (top, bottom, in a plant, in the center etc) and remaining there for an indefinite amount of time, only occasionally going to another part of the tank to do the same thing.
From what I've read here, I wanna say his water is just cold, but my room in which he stays is usually above 80 degrees. Right now it's 83 and even with the fan on it's really warm in here.
His eating habits haven't changed; I give him three Bettabites pellets twice a day which he pounces on (and visibly 'chews') as soon as he sees them.
I'm a bit worried also, because a few days before I changed his water, the bubble nest he had built started to shrink. I'm not sure if he just gave up, or if there is another issue at hand.
Appearance wise, he looks the same as usual, with the Bettafix (mostly) restoring a ragged pectoral fin. He has a few dark spots on him that he's had since I got him, but I think that's just part of his coloring. He's classified as a Crowntail "Electric Blue" Betta.
I've got a few pictures of him as well, but my camera and lighting qualities are terrible.
Any thoughts? Suggestions?
And he doesn't have a definitive name other than "fishy", "cutie", "sweetheart" etc.