water chem question for planted tank

I guess ill start with the basics, its a 37 gal all-glass tank with just
under 2 watts per gal, no CO2 injection yet.
pH 8.4
total hardness 250 ppm
total alkilinity buffer over 300 ppm (not sure cause it was drastically
darker then the highest value of 300 ppm).
NO3 approx 30ppm
NH3 and NO2 unmeasurable.

Well needless to say the tank was previously a home for african chiclids for
the last 9 years. Since I was down to the last 1 I traded him and cat and
pleco in and switched gears to a planted community tank, with 2 angels, 4
neon tetra, 2 corrys, 4 ottos and 3 neon dwarf rainbows with 10 camoba
looking stem plant (definately not camoba tho) and about 6 stalks of generic
hygro. Right now the plants are growing like mad, and algae is very low as
usual.

Now for the question, as you can see the fish would like the water with a pH
of alot closer or slightly lower then 7 and I am no where near that and also
it seems that many of the common plants would like a lower pH as well. So I
am wondering if when I start adding CO2 will I be able to get the pH to a
more accaptible range. Also I believe that the test my my hardness my be
accurate since I do believe our well water sits above limestone, and I do
not think our water would be phosphate buffered since I live on a narrow
isthmus of .5 miles between 2 lakes.

So anyways would CO2 get my pH down to a more reasonable level? Would the
use of pH lowering additives be a good idea? Or don't worry about it and
pray the fish will be fine, and be happy that my current 2 plant types are
growing like mad? Any sites or personal info welcome on overcoming this
problem, but unfortunately expensive fixes like RO systems are out of the
question for me, as I am quite limited on spare cash.

Thanks in advance