Im almost 5 months in with no measurable no3 or p04 in the morning.It really depends on what you want to do. My current tank is 265 and I went slightly oversized (9430) and while I don't yet regret it, it skims consistently, it would be nice to have some accumulation of nutrients, 7 weeks in and still no detectable NO3 and PO4 and I have battled dinoflagellates as a result. I think ideally you want some ability to build a level of nutrients you can control as needed with water changes and GFO, etc. I will see if heavily stocking fish can help.
I dose 3ml no3 and 3 mls po4 test 6 hours later and I get 1ppm no3 and .04 po4.
My tank is just using it up quickly. As long as I have film algae on the glass and everything is growing and looks good im ok and I dont worry.