Oh! Okay. Well that makes more sense. I didn't factor in initial setup cost.
Let's see what I've spent so far...
Gus (Betta): $4
Betta water (pretreated water for him to sit in until his tank was ready): $3-4
Setup (tank, plant, filter, gravel...) $30
Tetra AquaSafe: $4
Tetra EasyBalence: Given to me, but I think it is $4
Food: $8 (will eventually get bloodworms, but has to buy pellets to keep waste down)
Marimo Ball: $8
Toast and Boo (Ghost Shrimp): less than $1
Seashell (for shrimp to hide in): $3
API Amonia and pH testing kits: $15
Turkey Baster: $1
I hope I don't have to buy more than filters for a while...