Noob needs help with dumb questions.

Ok so I have been in reefing for over a year now and I was at the fish store getting some stuff for my reef and there was a very good special on a biocube 8 gallon (my reef is a 14) and my dad has wanted a fish tank in the kitchen for a long time and like the bio cube all in one cleanness of it. Soooo he bought the tank with my help and I told him I would set him up a fresh water if he payed.

We bought a piece of drift wood, sand and a small rock for the substrate and mixed them together to get the look we wanted.
for fish we have a cory cat fish,and two rummynose tetras.

For plants we have moss, and two other plant I think one is wisteria and the other kind of looks like temple. Both of those are planted in little pots and we left them in.

I told my dad Planted tanks need Co2 and other things but he told me he grew plants in his fish tank as a child and they did just fine.

So here is my question

how long will those go with out Co2 and what other things do we need to keep those plants alive?

we would like to put two mini frogs in along with neon tetras and hatchets.

THANKS