Let's talk nutrient import/export

[Potatohead]

Is it possible I just don't have enough coral load? The tank is mainly frags and somewhat sparse because I wanted to have fewer corals and grow them into larger colonies. I've had this theory for a while but not sure how to get around it other than things growing or spending a bunch on corals now and keeping them smaller down the road which is not my preferred route. There's a lot of light over the tank for only 15 or so frags and a decent sized hammer.