Remove what I think is calcium buildup

[rack04]

Good morning TFP. New here and looking for help diagnosing and removing buildup around my spa return feature. Any help would be appreciated.

 

[Rancho Cost-a-Lotta]

Welcome to TFP. The calcium buildup is a result of the constant cycle of the area getting wet then drying. When water evaporates, it leaves solids behind. Looking at the photo, it appears as the water is dripping from the spillway back against the sidewall. The spillway should have a groove cut at the bottom to prevent water from dripping backwards to the sidewall. Even with this groove, the wall may still get wet.

Try using a mixture three parts water and one part muriatic acid along with a nylon brush.