Congratulations on adding CO² you will see a great improvement. What PPM level are you going to be running? May I suggest you move the ballast out of the room? When the plants get bigger (and they will very fast) the heat it puts out could be a problem. No heat shield I assume because I donâ??t see any ducting removing the heat out of the room. Are you enhancing humidity too? When budget allows you should think of some side light too this will also increase the yield and quality of the buds.