Are you testing with test strips or a liquid test kit?
He has been in this tank since Feb. of this year.
How long has he been in the tank?
I have not had any probs with Drs. F and S. So far so good. I did not have good luck with ludwigia glandulosa. I did not get it from them, but it fell
Some fast growing plants can sometimes out compete the algae for nutrients and it will eventually die off. Feed less, frequent partial water changes,