chaeto not growing

[shyland83]

When i first set up my tank, the chaeto in the fuge was growing like crazy. recently it's not growing at all. Is it possible that there actually not enough nitrate and or phosphate in the water? nitrate levels have been zero, and i haven't tested phosphate but i do run a phosban reactor. if this isn't the problem, what else could it be? thank you

 

[Justjoe]

Your nutrients could be much lower now, which would slow it down.
Also consider dosing an iron supplement, it works wonders for macroalgae.