Nutrients low but algae growing? 20 gallon long

[Cbones1979]

While fighting dinos (and not doing water change for a month) I’ve noticed that my nitrates are constantly low. I have managed to grow free hair algae and I think the Dino’s are reducing while using a uv/h2o2/bactra7.
I have a 50 aqua clear fuge and a 20 aquaclear with just sponge and carbon.
I feed daily a cube and but nitrates just tested are at near 0.
Phosphates .24
Salinity 35 1.026
Ph 8
Alk 9
Cal 400

 

[2Wheelsonly]

The high po4 is probably driving the low nitrates. I had the opposite issue; when my nitrates spiked my po4 bottomed out and corals started starving, I started dosing po4 and nitrates went from 50 to 5-10 in about a month.