LPS help

[Octane13]

Recently noticed my frogspawn is not going well at all. About the same time I noticed the Hammer right next to it started expanding and looking great. I don't have any pictures of it fully expanded but in the second picture it would normally fill the section between the rock on the right and the hammer on the left.

Other than a 1.5 dkh swing over a two day period (forgot to dose) there have been no changes to the tank or its parameters for months. SPS looking great and growing like weeds. I did move it slightly thinking someone/thing was bothering it NOPE. Last night I dipped it just to see and nothing. I did remove a small yellow sponge from between two of the heads. Suggestions?

 

[IslandLifeReef]

What are your nutrient levels at? It could be hungry if they are too low.

 

[Octane13]

As of yesterday using redsea test kit for everything

Temp: 78.3
Sal: 1.025
ph: 8.3
Ammonia : 0
Nitrate : ~10 between two shades
Nitrite : did not test and usually don't
Cal: 490 - Usually maxes out the test kit and takes almost the week to go below 500
Alk: 8.3
Mag: 1480

using FRITZ salts