Chaeto help

My tank is 14 years old....I have always had high Nitrate and Phosphate issues, and have tried everything. I am now back to a refugium, and to that end am using my center compartment in the sump, lighted by a Kessil H160 Tuna Flora. I bought a baseball size (2 of them) bunch of Chaeto and now, a few weeks later, it has practically disappeared, and my Nitrates and Phosphates are as high as always.

I am running the light on the Grow setting at almost max intensity, for 16 hours/day.

A new batch of Chaeto is arriving today.

Any suggestions as to how to get it to grow and not die off so fast?

 

Is there sufficient iron in your tank? A lack of iron can cause Chaeto die-off. You could try dosing something like chaetogro, which should help replenish trace elements that chaeto needs.