Wow, that's quit a crop you've got there! I don't know what kind of algae it is, but I had an outbreak of the same algae on my rotala as well...not as lush as yours...but a pain nonetheless.
First questions are...are you using CO2 and, are you dosing iron? I ask because without CO2 in a planted tank using an EI fert regime you are very likely putting too much nutrient into the water for the plants to effectively utilize. In short, you're over feeding so the algae outbreak is on steroids. I ask about the additional iron because after my own problems I had read on numerous sites that too much iron specifically, can contribute to the problem.
What did I do to get rid of it?
First, I ensure a good balance between Co2 and light and keep my PH right around 6.8 to 7.0. I use NILOC's THRIVE liquid fertilizer which provides necessary micro ferts, but after using it at the recommended dose immediately had algae problems. I cut it back by about a 50% dose, plants are thriving and algae an almost non-existent issue. I mention it because of your EI regime, and without CO2 its probably too much. For the algae you have (and I as well, but less) I physically cleaned of as much as possible by rubbing the rotala leaves between my fingers and quickly vacuuming the loose algae out of the tank. While the filter is off, I then sprayed hydrogen peroxide (H2O2) on each affected plant underwater . BE CAREFUL, H2O2 will seriously injure any livestock you have if overdone. I killed my first Betta because I had sprayed the plants when they were exposed out of water during a water change and it was far too much in too little water. It burns the gills, there is no recovery. I won't do that again! Finally, I dose SEACHEM's EXCEL at the recommended dose and do a 50% water change every week.
Results were not immediate and I repeated this procedure over several weeks, but each week the algae was a little less than the previous week and after about a month or so I was free and clear. I have maintained the EXCEL treatment, and each week cut off any leaves that have significant algae on them. I also have AMANO shrimp, a couple of cories and several Nerite snails in the tank to help out. You'll hear from purists that using EXCEL is cheating, you have to id the core problem to really resolve it. Their right, of course, but I'm too impatient and prefer to cheat with EXCEL. I'll eventually wean myself off the EXCEL and see if I can control it naturally...but not yet.
Maybe others have some ideas, but this has worked for me. But again, you've got a pretty heavy crop there, it will likely take longer to get rid of than mine.