Sorry, didn't take any FTS before the treatment. This particular rock was one of the worst spots in the tank, though, which is why I picked it.
I did have a minor tank incident this morning. I spent the night at my GF's place last night. When I got home this morning I noticed a strange noise coming from the tank. The return pump was sucking in air. The cause of this was the bryopsis in the fuge was falling apart and getting blown out into the main tank. The trouble with that is there was an astrea snail in the output tube. The dying bryopsis got stuck on the astrea snail, restricting the output of the refugium, which caused it to overflow, which then caused the sump to run low. I moved the snail and pulled out the dying bryopsis from the refugium to fix the flow.
Then I did something stupid. I poured water into my kalk top off bucket (I should have just poured it in the sump directly instead), which mixed with the kalk at the bottom of the bucket. The bucket then pumped that freshly mixed kalk into the tank, making the water very cloudy. I did a 25% water change, but all 4 of my clams (3 crocea, 1 derasa) have been spawning today as a result of the kalk. Nothing else seems affected and the water is finally clearing up now. I know that clams spawn when they're stressed. I don't know if clam eggs/sperm are detrimental to the system. This is the first time they've spawned.