Buying a 20-55 gallon tank, what should I look for?

I have a 55 gallon. It is 48" wide, 12" deep, and 18" tall (not counting stand). So, if your space is only 47" wide, it would not fit.

I'm running a Penguin Bio-wheel 350 filter. I've been very happy with this filter. It does a good job and has been hassle-free. My tank was gifted to me by my step-daughter. It had an under-gravel filter. I promptly threw that away! With a good filter (such as my Penguin), it is redundant. They are also gross! Eventually, you will have to tear down the tank to clean under them, and when you see the crap that has been lurking under your gravel, it will give you the heebie-jeebies! I would much rather just do my weekly gravel vacuuming, and know it is clean. It's an ordinary task, like vacuuming my carpet.

I can't say for a certainty what the best brand of filters, hoods, or anything else is. I know I like my filter, and I know my hoods fit the tank. When I push the button, the lights come on. That's all I ask of them, so I'm satisfied. You absolutely want fluorescent, rather than incandescent, lights! They cost a bit more initially, but the bulbs stay cool, last for ages, and are much cheaper to operate. A much better bargain in the long run.

For gravel, your best bet would be natural, unpainted gravel. You have to think about what sort of bottom dwellers you will have. Some species, such as Kuhli Loaches, do much better with sand substrate, rather than gravel.

Plants also are somewhat dependent on what sort of fish you plan to have. I would buy the tank while the $1 a gallon sale is going on, and put it aside in a safe place. Research fish species you might be interested in before buying the furnishings.

I would keep the Betta in the 10 gallon, personally. They can live in community tanks, but he will be much happier by himself. Making bubble nests is just what they do to entertain themselves. It does not mean he wants to mate, it's just what they do when they are healthy and content. A 10 gallon tank is a palace to him. He doesn't need anything else.

Hope this helps answer some of your questions!

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