No where do you mention your Kh/Alkalinity/Carbonate hardness. This is ABSOLUTELY IMPERATIVE to know before you go injecting CO2. Kh is what buffers your water against wild pH swings, and is the measure of carbonate hardness in the water (the other main hardness type being 'General Hardness' or Gh)
It sounds liek you have extremely soft water, which will require you to add baking soda (the cheapest method) to raise your dKh up to 3. A dKh of 3 will raise your pH a little, I'd guess maybe 7.2 ~ 7.4. The CO2 will then lower it again.
Quit with the 'cheap pH up/down stuff' as its more expensive than baking soda, and pH down is just a bottle of phosphoric acid.
Ditch Stress Coat in favor of Seachem's Prime (stress coat has a ton of useless, polluting crap in it, like aloe vera. name one fish that uses aloe vera in the wild to maintain its slime coat. If you can, and have sources, I'll paypal you $5)
There's also no reason to use Cycle.
off topic, don't expect too many people to email you from the forum. We come to the forum to share all our knowledge, not exchange secrets in private.
If email is your cup of tea, there's an Aquatic Plant Digest mailing list you can subscribe to, and get about 50 emails a day to your inbox
I found it was too much to wade through, and thus stick to forums that I can pick through more easily.
you might want to pay $13 a year and subscribe to Tom Barr's http://www.barrreport.com/
I don't subscribe yet, but I hear its a great resource.