Plants and lights needs

I bought a used tank with stand, hood and light fixture, aquarium dimensions are 36" X 12" X 18" which is I believe is a 33 Gallon tank.

I get exited and the next day I went to petsmart and I get two amazon swords, one water sprite,one flame moss and a red and green plant with short leaves .I know made a mistake because I didn't read the plants requirements before I bought them. the guy at petsmart also recommended to buy some chemicals tablets for plants which I believe they are fertilizers ( I read the instructions on the bag and it says to put one tablet for each 15 cm radius ). my light fixture is 36" but the light fluorescent tube itself is 23.5" long. the lamp wattage is 17 Watt and I can't install more than one light tube in the hood. so basically my WPG is 17/33 = ~0.5 WPG.
After doing some research I found out that the amazon sword and the water sprite needs more than 2 WPG.
My questions:
1) Can I keep those plants without CO2 system ( I have no idea about CO2 and how it works)
2) Is my light enough to grow those plants (except the flame moss which I believe will do well with the current light)
3) if I have to upgrade my light, can I find a fluorescent tube lamp that is 30, 60 or 90 Watt without changing the whole hood.

 

Your red and green plant is most likely ludwiga. You can keep them without co2. The light on the other hand is inadequete and I suggest you look into another fixture. The marineland aquatic plant fixture would work. Good luck

 

The tablets are known as root tabs. They will help the Amazon Sword a lot because Amazon swords are heavy root feeders. Yeah your plants can grow without co2, can you post a pic of the red and green plant? It can help. Do you know what Kelvin rate is your bulb? A 6500k bulb should grow all these plants very well, the plants you have are considered low light plants.
Edit: also Watts Per Gallon doesn't work as it's an outdated method and isn't really reliable.

 

IME, amazon sword is a medium to high light plant. I'd try to find a good T5HO for them. I have dual T5HO with a 24 watt 6000k and a 24 watt roseate on my 20g. Par is more important than watts, though. Like red spectrum or blue spectrum, ect.

As for your fertilizers, I use seachem root tabs. I put one under the plant base. I've never had a problem with root burn.

As a word of caution...amazon swords grow huge once established.

 

Amazon swords do grow very big. When I moved my Amazon sword in my 60 gallon, it had roots spread out all over the tank.

 

Thank you guys for the useful advices. actually I don't know the KELVIN of my light because it came already installed, and the writing on the lamp are almost gone.
Here are some pics.

 

Yep your red and green plant is ludwiga

 

From the pictures, the light seems like it's good enough for the plants. It's bright enough to help the plants grow healthy.

 

Thank you guys for the useful infomration