Too much CO2, please advise

Hello all,

     In my attempt to experiment with CO2 injections I have set-up a 10
gallon to see the effects.  My tap water has a pH of 7.6 and a KH of 4.  I am
using a AquaClear Mini for filtration and bubbling the CO2 into the intake
tube.  In order to find the effects on the water I ran the CO2 (yeast method)
for a day.  It dropped the pH to about 6.2, thats alot of dissolved CO2 isn't
it?  I figured that it would go down after I but plants in the tank.  So
today, I placed the gravel (no additional substrate yet) and the new plants
in the tank ( 3 bunches of Green Hygro, 4 bunches of Rotala,  some Anachris
clippings and about 4 small Corkscrew Vals).  In doing so, I replaced about 2
gallons of fresh water.  When I turned on my 20w Triton and 15w Penn-Plax
lights, the plants almost immeditately began to produce bubbles (Oxygen, I
assume).  First of all, I've heard about this happening, but have never
actually seen it, or hoped to achieve it.  About 9 hours latter, I tested the
pH and it was still 6.2.  I don't believe that there is much outgassing of
the CO2.  My question is:  Is my CO2 count ever going to come down?  Is too
much dissolving?  I want to put some algae eaters in, but I think this pH is
way to low.  Any suggestions would be wonderful.  Oh, I am using 1 tsp of
yeast to 1 cup of sugar.

     - Keith