how much water flow/current is at the bottom ground level?
maybe what I'm wondering is it adequate enough to "comb" the ground cover of debris, it seems much of the algae is around the carpets. Just throwing some ideas out there it does sound like you have adequate filtration. The stem plants look more mature in the second pic, I'm also assuming more stems in the aquaria could possibly reduce overall circulation within the system. Its a beautiful tank would hate for you to give up on it.how could I measure that? I have high flow up to 2500 liters per hour in my filter