Corals won't grow.

[Stevenjc57]

Acan, bottom right, zoas, bottom left, hammer top right

 

[Stevenjc57]

Where should the acan be at? And what kind of flow?

 

[Stevenjc57]

Reef roids, just like any other food will increase your phosphates, and that's why people feed only once or twice a week. If you change your water frequently or have some kind of phosphate control, I'd say go for twice a week. Spot feeding can definitely help but I personally find it unnecessary.

That makes sense, thank you! I'll try once a week then

 

[ScottB]

OK so you have conflicting advice now: too much nutrient OR too little. Welcome to the hobby!

Pick up two more testing kits. My go to favo(u)rites

Red Sea for nitrate:
https://www.amazon.com/dp/B00BAVVD6...bf71-6c5cc9c12b5d&ie=UTF8&qid=1540855847&sr=2

Hanna for Phosphate/Phosphorus
https://www.amazon.com/gp/product/B003UNK3I8/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

From the picture, I don't see much algae, but see some red colors on the rock. Is the rock covered with a red film or is that just the rock color? Sand looks pristine. Did I miss the usual question: How old is this tank and the rock?