Help: Small unknown brown bug infestation
So I had this tank set up back in January before leaving for college and left my family members to keep up the routine of water changes and nutrient dosing. Everything was going according to plan until about late April when the staurogyne repens started losing their leaves but not their color and we just assumed maybe the snails or fish were eating them or something. I recently came back home 2 days ago and noticed that there was a bunch of these microscopic tick like bugs on the repens and all over the substrate.
I was planning to remove just the top substrate of the tank but there's an issue of them being on other plants as well.
I never encountered anything like this before and have no idea what I'm dealing with. Some advice or treatment plant would be very much appreciated since I'm quite worried.