Okay, first things first! I'm dumb. A week ago, after being impressed by all the fish in the pet store, I purchased a 10 gal starter kit, 5 "feeder" goldfish and a male betta.
My thought process was that I would learn the intricacies of maintaining a fish tank with some hardier species, and eventually switch out the goldfish for some others. The only advice given to me was "rinse everything in water before setting up your tank". So I got home, rinsed everything my tub (didn't use soap, don't panic), put the gravel in the tank, filled it with water, added a conditioner, put in the decorative rock, planted the the plants, set up the filter and heater, attached the thermometer, noted the water was 78 degrees, and dropped the fish in. The betta and goldfish got along without any undue aggression towards one another, and everything seemed peachy-dory.
Now, I have done a vast amount of web-based research and realized the magnitude and prevalence of the mistakes I've made.
First, I have 5 goldfish. I like them, they are active, colorful, and generally interesting. I wouldn't mind keeping them, except for the fact that they have the potential to grow past 12 inches! With that in mind, there's no way I can keep them long term! I asked the store if they would take them back (I don't even want a refund, although that would only be about $0.80 anyways), and they said they don't take back fish. They may have been "contaminated". I have no idea what to do with these fish! I feel awful that they're going to outgrow my tank, I can't return them to the store, and I don't like the idea of introducing them to a nearby lake/pond/whatever. I could use any suggestions on this one.
Second, the filter that came with the tank generates a considerable current that grossly disturbs my betta. For the short term, I bought a "1 gallon under gravel filtered corner tank", transported him and a plant into that, and he seems much happier. My concern with this new tank is that I can no longer moderate the temperature in any stable fashion. I've considered suspending it in the 10 gallon tank as a divider, but I don't want this to be a long term solution.
Ideally, I'd like to remove the goldfish from the 10 gal. tank in some ethical way, return the betta to it, and find some other small fish to add.
Any suggestions would be appreciated!