Nice Shots. Lots of nooks & crannies & lots of room to swim.
Do you have your Koralias on a timer or on steady?
I have the same setup with 2 #4's. Originally had them on a wave timer but they failed. I don't think they are designed for on/off use, (wish I knew that when I purchased them).
Bought 2 new ones, put them on steady & they are OK.