Grover, it looks to me like you're having decent success! You wouldn't want wild growth in 15g tank anyway.. I've never really had what I'd call a "planted" tank, but I keep several tanks with lots of live plants. FWIW, all I've ever used was plant suitable T8, T5 or LED lighting, liquid CO2 and readily avail liquid ferts at times. I run timers for the lighting and typically keep them on 7-8hrs/day.