Well, I have a male betta fish (Haven't found a good enough name for him yet) & I noticed something odd (Yeah, I know all questions must start that way!
Well, when I first purchased my fish, he was purple & red with dark (almost black) scales on the head.
But after I brought him home and acclimated him and put him in his bowl, I noticed his colour had changed. This is how he looked.
Now, today, in the morning I noticed he had made a bubble nest! (Yay!)
Bubble Nest Picture here!
But then I saw something weird, his colour had changed back to what it was when I bought him. I bought him from the pet shop around 4-5 days ago.
This is how he looks now.
Current picture here
Although in the picture he looks blue & red, he's actually purple & red & black (on the head).
Now, I'm guessing this is why:
The pet shop had kept him in a small tiny partition in an unheated aquarium. And the pet shop has an air conditioner maintaining temperature at around 76-78 °F.
When I brought him home, I kept him in a room that has no air conditioner and so, the water temperature was higher.
And it rained heavily today & that's probably why the water temperature went down.
So my theory is that the temperature affects the colour of my fish. But I may be wrong. So, please advise me on the matter. And I couldn't see any shiny layer on his scales, I hope this isn't velvet.
What size is your tank? 5 litre
What temperature is your tank? 79-82 °F
Does your tank have a filter? No.
Does your tank have an air stone or other type of aeration? No.
Is your tank heated? No.
What tank mates does your betta fish live with? None.
What type of food do you feed your betta fish? Micro-pellets and Bloodworms alternatively.
How often do you feed your betta fish? Once daily.
How often do you perform a water change? Once a week.
What percentage of the water do you change when you perform a water change? 20%
What type of additives do you add to the water when you perform a water change? Solutions to remove Ammonia, Chlorine and Nitrates.
Symptoms and Treatment
How has your betta fish's appearance changed? Colour (purple-> blue-> purple) & blackish scales
How has your betta fish's behavior changed? Not changed in anyway.
When did you start noticing the symptoms? Today.
Have you started treating your fish? If so, how? Nope.
Does your fish have any history of being ill? Nope.
How old is your fish (approximately)? I got him a couple of days ago. Seems less than a year old. Maybe 8-10 months (just a guess).
P.S: I'm from India, so the temperatures here are quite good for tropical fish (especially bettas) so, I found it unnecessary to invest in a heater. Maybe when I do think its necessary (Read: when I have the money), I'll get a heater and a filter & maybe even a bigger tank.
Thank you so much for reading and replying, I appreciate any help or advise that you can offer me! :)