You have a dilemma! Shrimp don't breed well with high CO2 in the water. And, HC doesn't grow well without high CO2 in the water. (I'm not sure what Downoi requires, other than soft water.) I think most shrimp keepers, who want their shrimp to breed, just do without any plants that have to have good CO2 to grow well.
I think you will have enough light, with 9-10 watt bulbs, to grow anything, but only if you also use good CO2. Take away the CO2, and you will limit your plant choices. Add more light without more CO2 and you will have algae problems.
Hoppy, you are right. There is a huge dilema. Our plan was to run CO2 on high for the first 2 weeks while transitioning the HC from emersed or submersed. On our 3rd week we would start slowly tunning it down and hopefully by the end of the month, we hope the HC would still do well without it. We have read a few forums where people can grow very beautiful HC's without CO2 so we are really hoping we can do the same. Nevertheless, thank you so much in assisting me on this matter. You really are a life saver : )