Thanks all. Sounds a little encouraging. I looked up more on hard water plants & it seems the amount off species is less than soft water. That would not be a problem for me. I would be happy with 3 or 4 species as long as I could control the algae. Not sure if I would dare run a couple of soft water plants in as well CO2 or not they would probably grow better emergent.
I am still not sure at what ph or alkaline point the Free CO2 gas would turn into bicarbonates if I ran pressurized CO2. That would be another interesting experiment. Right now I am leaning on trying a straight up hard water tank without pressurized Co2. How much difference would it make at higher Ph levels???? How many watts should I run with say T-8s with 6500k bulbs on a 55 gal in this application? I have the soft water tanks down well but the hard water tanks are a whole other world for me.