over stocking

Happy holidays Reefers, I wanted to just get a sanity check on my tang stocking plan for my upcoming tank upgrade I currently have a marine land 90 gallon with a single Yellow Tang along with some other tank mates standard clowns, six line 4 choms. Im going to be upgrading to a waterbox 7225...

I need to find a way to raise my nitrates. 75 gallon tank with about a 30-some gallon sump. I have four smaller fish in it right now and about 20 frags. I thought about dosing and might try to go with brightwells neonitro to do so but according to their website it will also lower my phosphates...