Reducing NO3 to squeeze red out of plants can be tricky because you have to have low levels (<5ppm) and hold the balance. With your tap water NO3, you would have to use RO or distilled water to dilute the tap water.
There are nitrate reducing filter media, but these are not recommended for planted tanks as you could drop to zero unexpectedly, which would be bad for your plants. Prime does not reduce nitrates. It only binds them up for a day or two. However, Purigen can reduce the organics, created by fish and plants, that will turn into nitrates. Purigen does not remove nitrates that are already there, it just helps reduce the creation of nitrates.
Root tabs release nutrients in uncontrolled levels and are not necessary since all dosing can be done via the water column. You should be dosing your water column anyway to ensure complete nutrient levels.
So, my advice would be to do two 50% water changes, a day apart, remove the root tabs and replace with a balanced fertilizer, add Purigen to your filter (which may be eliminated if you get your NO3 to levels where you want them) and then see if you can maintain NO3 where you want it for a couple of weeks. If you still need to reduce, consider an RO unit or distilled water to dilute your tap water during water changes.