Rick wrote:

"LeighMo" wrote in message
That's a really neat setup. A good level of light for both tanks.

You might have more success injecting CO2 into one of the 20 gallon tanks,
just
because DIY works better on small tanks. And since you have two, you
could
compare them side by side, and see what the effect of CO2 injection is.
:-)

I'm going to try that. I have checked the PH levels on my 77g since I hooked
up the single 2 liter DIY CO2 systems several days ago and there has not
been any change at all although I don't know how long it would take to
change PH. I'll be setting up my double gallon jug system next week when I
get back from Calgary.

Rick,

Please report back with photos-that would be a great case study for all the
people interested in adding CO2 to their tanks!