Hi Sicamore Tree,
That is a lot of light using only DIY CO2. When I first started I did DIY with about 2 watts per gallon and I had to keep my photoperiod very short (5 hours) to avoid plant nutrient deficiencies and algae issues.
I would suggest dropping down to one bulb if possible and start with a 5 hour photoperiod. Old leaves will not change but see how new leaves that are formed are shaped.
Here is an excellent article on a "Light Limited Aquarium"
by Tom Barr and how to adjust the photoperiod for optimum growth with minimum algae.
45 Gallon using Flourish Comprehensive, Excel, and DIY CO2