And it's evidence that the water changes for removal of nitrates are only masking the bigger issues , if your nutrient rise is greater than what you remove then you'll slowly accumulate. Something as simple as 0.5ppm is 3.5ppm in a week and 7 in two and so on and so on. Sometimes the rise is so small it takes months to even notice you've been going up.
Adding more nitrogen sources simply speeds all this up more so.
Water changes have great advantages but I don't consider nutrient export one of them maybe a bonus to be had but certainly not it's best feature
You'll get there attack in small battles and wear your enemy down step by step, there's no rush to do this unless you feel the tanks inhabitants are in danger or decline
Good luck buddy
Denny