I have a heavily planted 29 gal tank, and the plants are doing very
well. 65 watts (Custom Sealife "Britelamp"), DIY CO2, KH about 5, pH
6.8-7. Flourite substrate.

I experimented with all sorts of DIY CO2 setups before coming to the
one I have now, which is very easy to maintain. Two 2-quart juice
bottles connected by a "T" in the tubing, I swap each one out about
every 2 weeks. Hagen "natural plant system" diffuser. AquaClear HOB
filter ... a lot of people will tell you that a HOB filter will
generate too much surface turbulence, but that's not true in my case
.... as a matter of fact, I have an airstone rigged up under my diffuser
to blow off excess CO2. I use a pH controller which turns on the
airpump when the pH gets too low, but the airpump runs mostly at night
and probably a simple timer would work too.
Low maintenance, no worries!