20 gallon tank

keep in mind that many of the "starter kits" contain 20H's.

if you want a 20L, chances are you will have to get all fo the equipment yourself, rather than buying a kit. this is usually better in the long run anyway.

for a filter, get a Penguin 150 or 200

for a heater, get a 100 watt Visitherm stealth heater.
 
Thank you all for your help. I was going to buy it all on my own. The starter kits are the 20H and after reading all of your comments, I am going to go with the 20L. Thanks for listing types of filters and heaters. That will come in handy!
 
my personal opinion a 20 long is better and a nice size to start with so that you arent out a bunch of money if you decide the hobby just isnt for you but i will have to agree with BoredAgain the smaller tanks are harder to take care of than the larger I have 2 55 gallon tanks and a 10 gallon tank that is suppose top be my daughters but i spend more time on the small tank than i do the 2 55 gallon tanks. Well that is my .02 cents worth good luck and have fun!!!!!
 
My 20g Long is my first real set up tank. I prefered it over the regular 20g or 20g High b/c fish don't relaly swim up and down rather left to right and right to left so I prefered a longer set up. With a longer tank it allowed me do more things with it and got into the planted tank interest. Yes, if you do get a 20g Long you don't get a complete beginner kit but you can pick and choose your preferred equipment to build a nicer tank. As for fish, the inhabitants is in my signature.
 
AquariaCentral.com