Well you have to admit, they're much better living with me then probably dying at the pet store. I don't think one of mine, butterface, would have lived much longer. His water was really bad and I think he might have breathing problems from it now :/
Just because it is better does not mean it is good enough. You really MUST be changes your water 100% every other day in your tank. Once a week is far too little. The dangerous stuff in the water is clear, you can't see it. And often times a betta will "seem" and "look" fine, but most issues start internally.
Well, turtle10, if my bettas die prematurely then you'll be right.
But turtle10 is right... not only if your betta dies. Not trying to bug you here, it's just that it hurts a fish to be in ammonia. It's like if I kept you in a closet (not that I would, I'm no creeper! :P) and left you to breathe in and sleep in your filth, while only letting you out once a week to clean your closet up, then put you back in. You get what I'm sayin'? I'm not trying to sound like a nag, but you really need to up your water changes. In a tank that small, water changes dont take long anyways ;)
I would notice ammonia poisoning. There are symptoms.
The symptoms come AFTER the ammonia starts to affect them. So no, you actually would not notice ammonia poisoning, not until it has already damaged them Why won't you just do the water changes? The ammonia really does build up that fast. Your betta is suffering when you let it go that much, do you realize that?