Test your water, that will help.
Ammonia, nitrite, nitrate, phosphate, and iron.
If you are missing something, and have way too much of something else that will cause problems.
The plant growth will slow down, and algae will grow faster.
I have auto dosing set up.
I test parameters before a water change to see how things are going.
If something shows up too high or too low, adjust the dosing. Once you have it figured out, how much of whatever to add whenever. That really doesn't change that fast. It took about a month of plant growth to require a modification to the dosing schedule.
But I don't have CO2
I dose the tank according to the amount of water change water that I am adding as it is at 0ppm as far as fertilizer goes.
I bring the new water right in the middle of whare phosphate, potassium, nitrate, and iron should be.
One water change a week is good, unless you have a overstocked problem, that you don't.