I had tanks for years and really wouldn't suggest anything smaller than a 10 gallon. Something along the lines of a twenty would be better. The larger the tank, the easier it is to care for if you have the proper filter system. You will have to do a little bit of work every week or every couple of weeks, but if you keep it up that way, you won't have a huge mess on your hands.
Also it has alot to do with what kind of fish you put in your tank. Get a couple of bottom feeders and they'll keep the algae from building up on the glass. It wouldn't hurt to buy a few books on the subject...there are some really good ones out there. I agree with those who say stay away from gold fish...they are very messy! If you get a tank with a heater, you can have more of a variety of fish as most of the fish for freshwater tanks require warmer water.
It's a wonderful hobby and can be alot of fun. I always thought that one couldn't get attached to fish as pets, but I was amazed how attached I did get to the fish that I had for years and years. They didn't fetch or snuggle, but they were great pets. Some even knew when I was coming to feed them and they'd be up at the top of the water waiting for their dinner.lol
One other suggestion is to not buy your fish from a department store (Walmart, etc) but to buy from a pet store. The pet store I bought fish from guaranteed my fish and was great at giving advice that I desperately needed when I was a novice. I find that if I bought from a dept. store, they had people working in the department that didn't know much about the fish and also would not give a guarantee.
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