I already have the frog, and he is a male, so he's only gonna get 3-3.5". Since this tank is 23" and he is gonna be the only inhabitant plus a snail or two and a bunch of plants I figured it'd be ok. U guys think the light will be good for a low-tech tank? Thanks.
The light is pretty dim but low light enduring plants will probably be ok. I think the frog will simply uproot them when moving around, so plants like Java Moss or Fern attached to wood or stones would be best. Maybe invest in a better light if the plants are really what you are wanting to see grow better.
I used a CFL type system with a bulb in the 5500k range to keep plants in the 5 gal.
More importantly is the quality of filtration. Larger, with good water circulation is better. I had an adjustable flow canister filter at the time so I could adjust flow for my needs. Something that turns the water over 5-10 times an hour will be sufficient, and yes water changes would be 50% or more at least once a week.