It really depends what kind of set-up you want. Low-tech, medium-tech, or high-tech.
Low involves about a single wpg
, watt per gallon, and uses low light plants like java moss, java fern, Anubis, ect. You don't need to use Co2
or fertilizers for this.
Medium is a step up, using around 2 wpg
. At this point you could experiment with DIY Co2
and store bought fertilizers like Excel.
High tech gets a expensive, needing 3+ wpg
. They are normally used with pressurized Co2
, but not always. They use a number of different fertilizers to nail specific needs for specific plants.
I'd suggest starting with low, obviously. It's the cheapest and most easy option.