sorry got busy yesterday
At this point we know you have good light. We know you have a decent fertilizer. We know you have Pressurized CO2
What we don't know is if your plants are using up your ferts quickly (not enough) or if there is too much. Hence my request for you to at least measure N. You may need to add more, or even less... This is something you should monitor throughout the week. By the time you get to your next water change there should be some build up of N to measure, usually around 10 ppm - 40 ppm. If you read 0 by weeks end you need more. If you read over 40ppm I would think less.
We don't' know if you are getting enough CO2 by measuring your PH before lights on and then again towards the end of the light cycle to see if your are getting a solid 1.0 PH drop indicating good CO2 saturation. If CO2 is low then some fertilizing will be wasted and would probably feed algae.
The other thing to be able to play with is light cycle / intensity. If you have a build up of fertilizer you may want to run the light a little longer. If you have 0 N to measure then your light intensity may be too strong and the plants are using up ferts to quickly. The balance with light comes from a combination of time on, and how close the light is (moving light up and down changes the overall intensity)
so basically we are back to looking for these clues. DO we have too much fert or too little, do we have enough CO2 or too little, and is our light to intense or not intense enough.
I wish it could be as simple as pointing out any one thing but its always about tweaking this and that and finding the balance for any given tank