My sister was doing everything right.. admittedly in a 1/4 gallon tank, but.. she changed the water twice a week, fed a bloodworm or a flake every other day... treated the water and let it sit to adjust to room temp. Cern, after a book character, had been with us for a few weeks, almost a month.

This evening we noticed that he had a bit of white fuzz and was fairly lethargic, so on the parental unit's recommendation we added about half a teaspoon of kosher salt to the new water when we changed it.

About half an hour later he was dead.

I was offering to her to drop her by PetCo to buy her a one-or-two gallon tank for next time, and she just said "And if there isn't a next time?"

Noo! We've lost a future fish person!


This on the same day that we've lost one of my mother's two remaining angelfish!

Sorry to hear about your family's fish. It's always so sad when they pass away
I must admit that sometimes after some of my fish died, I felt like I was never going to buy anymore fish ever again since I find it hard dealing with their deaths especially when they've been with me for many years... but.... I always ended up buying new fish (so hard to resist ) so maybe you haven't yet lost a future fish person!!

That's true! That's very true, maybe eventually she'll change her mind.

And even so, if she starts with a ten gallon something next time, theoretically she could have minnows or tetras instead..

I'm sorry Even though she was changing the water often, there are other factors such as small room for error, stress from waterchanges, and temperature that could have contributed. Since you mention white fuzz, he was probably weakened by those factors or was sick from the petstore and caught a fungal infection.

You mentioned that a couple angelfish died the same day? I'd check water params on the tank and tap water to be sure nothing weird is going on.

The angelfish is in a separate tank, definitely.

The parameters in the angelfish tank tested out as fairly similar to what they have been, no ammonia, no nitrites, 6.3 pH (a little higher than it had been, before was 6.2 or 6.0)

80 ppm nitrates, but, she changes out water every two weeks, and filter material every other water change.. so never all the filter material at once.

I don't think my mother did a water change on the angelfish today..

I did a water change on my goldfish today, and so far, so good. *knocks on wood*

So maybe not the tap water?

sorry about your sister's betta. Sorry for your loss. I also a while back lost a beutiful purple female betta to the same thing.