uh oh clown host - hammer diseased?

[Scarfish]

have had this coral for 1.5 years. My first coral in the tank (running 2 yrs now). Many branches on this piece (~12, I'm guessing).

Noticed 2 days ago 1 branch was gone (totally white). Today...2 more branches look retracted like they may go next.

I've experienced this before on other corals in the past - most recently in late Feb - early March when my whole frogspawn was lost this way. I hate this. What the hell?

Last night did a 6g water change...
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90g Tank

Nitrite = 0
Nitrate = 10
Calcium = 325
Alk = 9.0 dKh
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NOT GOOD, cuz this is my host for the ocellaris clowns. they spawned for the first time less than 2 weeks ago. They'd be devastated!

I'll take a pic.

SHOULD I CHOP OFF THE 2 pieces that look like they might be diseased???

 

[Scarfish]

only thing that has changed in the tank recently is

*there is more cyano on the rocks in certain places
*my toadstool is doing one of it's cocoon phase things...normal from what people tell me. It contracts for 2 days then peels an outer skin. It's just about done peeling now.

no fish added recently...nothing really added to the tank in the past few months

 

[~Flighty~]

Did you move anything around or change the direction of flow? I put in new flow and everything that is downstream of anything is having issues.

 

[Scarfish]

moved 1 powerhead but I don't think it would have affected it honestly

 

[NateHanson]

That's too bad. Hope it can be reversed.

Your calcium is awfully low. I'd bring it up to 400-450. Not sure if that's enough to be causing your problem with the hammer.

When the frogspawn died, did you notice any gooey brown stuff on the dying heads, or other signs of infection? Are you seeing anything abnormal on the hammer heads?