Just so you're aware, the previous post was what I'd do if I could do exactly what I wanted - 4WPG would be great, but it's not essential. You can keep some plants at as little as 1.5WPG. Likewise, CO2 isn't an absolute must - lots of people keep 'low maintenance' tanks with low to medium light levels and no CO2.
PMDD - it's DIY fertilizer, stands for 'Poor Man's Dosing Drops' I believe. My current mix (which differs a bit from the standard PMDD because when I made the batch I was having trouble finding KNO3) is listed in my tank specs - just click on my signature if you'd like to see. Try Googling PMDD and you'll see lots of stuff about DIY fertilization.
CO2 is needed if you're using high light and fertilizer - I think of them as three sides of a triangle; without one, the others can't be used to their potential.
I use DIY CO2 - plastic 2L soda bottles filled with water, 2 cups of sugar and 1/2 tsp bread yeast. Just drill a hole in the cap slightly smaller than the diameter of airline tubing, and pull the tubing through. You can silicone it (to prevent leaks) or not - I find if the hole's small enough you generally don't need to - and then attach it to a check valve and run the airline into the tank. You can use an airstone (but keep it clean or you can get back pressure and the bottle will explode) or feed the airline into a filter intake or bubble counter. There's LOTS of stuff online about DIY CO2 - different methods, mixes and diffusers, all variations on a theme.
If money was no object I'd be using a CO2 canister - I DIY because it's affordable, but it takes 6 bottles to get the level of CO2 where I want it in my tank so it's a bit of a PITA.
To figure out how much CO2 is in the water (how many ppm - parts per million) you need to know pH and KH - I use the calculator from
Chuck's Planted Aquariumwebsite. Anywhere from 20ppm - 35ppm is what I aim for.
I wouldn't do stuff based solely on what I personally like - wait to see what others say. We all have different ways of doing things that work for us.
