What trace elements could cause my coral decline

[Troylee]

For everyone saying alk I would disagree… mine bounces all over.. what’s really funny is I set up a frag rack in my sump and it dumps sodium hydroxide and 3-4 gallons of kalk on the all day and night and those frags are doing great lol.. you can see how much my ph fluctuates as the probe is next to the frag rack… these are all sps btw.

 

[wasabi bean]

I just measured phosphate and it is back up at 0.4ppm, last measurement of 0.08 might have been false but if not why is my tank fluctuating so much, it is about 280 litres with the sump, and is coming up to a year old, could it just be because i have added fish back in two weeks ago and the bacteria population needs to ramp back up or is it something else that has happened to you before?

 

[Troylee]

A lot of that depends on the time of day you test and how much you feed of what and when!

 

[rishma]

This is a tough puzzle with the pieces on the table. I’d really only be guessing at the possible cause of coral health issues.

The most concerning to me would be a relatively rapid drop in phosphate, if that is real. Fast phosphate reductions seem to be frequently associated with coral health issues. The absolute value of phosphate seems to matter less (within reason).

Fewer issues with rising phosphate. I recently dosed enough to raise mine 10x by accident…no problems.

 

[Shirak]

I am curious about light. In the white light photo the zoa seem a bit pale and stretched out?

I think the parameters and nutrients, especially phosphate bouncing around isn't helping. .5ppm to .08ppm PO4 in less than a month is pretty wild. Especially since it was .2 -1ppm for a number of months prior to the fast drop.