co2 fizz tab newbie

Well, let's have a look at the situation:
How much light do you have over this tank?
Unless you've supplemented the light that came with the tank, you probably don't have enough to have a great deal of success.
More importantly, while supplemental CO2 will help any planted tank, it's probably not necessary in your case.

If you do want to dabble in the CO2 world, have a read through the CO2 sticky in this forum, it should give you a good grasp of what to look out for, Len really knows what he's talking about.

Also, while I've never used them, the idea of "fizz tabs" makes me think of alka seltzer, which I don't see as being a very sustainable way of providing CO2 to your tank. Look into DIY CO2, it's cheap and reasonably easy. It takes a little work to get set up and running to your personal specs, really it's a bit of art form. Once running though it's quite easy to maintain.

If you're not handy, don't have the tools, or just plain don't feel like gathering and assembling all the pieces Hagen sells a "natural CO2 system" which is basically a manufactured version of a DIY setup. This apparently works quite well on tanks <20g, which is you. The bubble ladder, paraphrasing DJLen, is the best reactor for the money.

The 'Fizz Factory' is a CO2 bell, a piece of airline, and a cup with a lid. You place the bell inside the tank, and then to fill it with CO2 you put a tablet into the cup, which has a piece of airline in the lid that attaches to the bell, and add water. It fizzes, CO2 runs through the airline into the bell. When the bell is full of CO2, you disconnect the cup. When all the CO2 has left the bell, you add more. I think DIY would be way easier - it takes about 60 seconds to prepare the mix and it lasts for two weeks.

I used to use Jungle fizz tabs. In fact, I still have some lying around somewhere gathering dust. The bottom line was that they really don't do much of anything, and I thought it was a colossal waste of money. I switched to a DIY system. It is very uncomplicated, and my plants stopped dying and started growing once they were getting a steady source of co2. It made my fish happier too, because they love the dense plant growth.

What I have is just a 2L juice bottle with a cup of sugar dissolved into water with 1/2 t. of yeast and 1/2 t. of baking soda... filled 3/4 full. It lasts 2 weeks or so, easy to mix up another batch when the old one is done.

I just drilled a hole into the bottle cap and stuck a silicone line into it, aquarium sealant to make it airtight. The air line goes through a check valve (to keep water from backing into the bottle) and into a powerhead. Though, I used a ceramic airstone for the first couple months, and that worked just fine.