Maybe cease w micros altogether for a few weeks and see how the plants respond.
I know that co2 distribution down to substrate level can be very challenging in deeper tanks. I've even had flow-related problems in my tank which is only 12" tall, but not until plants started filling in more, which obstructed flow in critical areas that previously had plenty of flow.
A trend I've noticed is that people with deeper planted tanks will have a powerhead placed down low in the front corner, blowing directly over the carpet to make sure there are enough nutrients being delivered constantly. If the carpet doesn't grow at the fastest rate possible given the amount of light, that's when algae will start showing up.
Just this morning I moved a powerhead from the right rear corner to the bottom front left corner to see if I can get better results from the star repens which is somewhat walled-in and located in the spot most susceptible to poor flow.
Even if flow is not an issue now, this can eventually change. I would recommend trying to get all of the equipment working together with the same flow pattern. Turn those two circles into one giant oval, and find a way to make sure there is plenty of movement in a single direction near the bottom, flowing directly over the carpet plants.