Algae help needed

[DKoKoMan]

I don’t think your nitrate and phosphates are truly at zero “0”. If this was the case algae wouldn’t stand a chance and your chaeto would essentially die off. Do you have any photos of the tank in it’s current state?

[ReefMadness]

Originally Posted by DKoKoMan

I don’t think your nitrate and phosphates are truly at zero “0”. If this was the case algae wouldn’t stand a chance and your chaeto would essentially die off. Do you have any photos of the tank in it’s current state?

agreed. the true ppm of your phosphate and nitrates are trapped within the algae which is quickly consuming what is available to them.
this is a common issue with new setups that lack the biological balance and stability you get a couple of years in. a lot of headway can be made by manually removing as much algae as you can prior to water changes and then sticking to your low input of nutrients. be aware that it isn't going to happen quickly so settle in and keep dedicated to the effort but also watch your coral as underfeeding the system has its own negative results.