SPS struggling...usually evident on montipora first, then others.

[polleke]

In my opinion it was the low NO3/PO4 possibly in combination with the high KH. So unless this Coral Colors also contains aminos or other food that will not have helped.

 

[BrentH]

What's your perimeters now?

 

[BrentH]

So u had high kh and low po4/no3? And u didn't know it?

 

[dg3147]

So u had high kh and low po4/no3? And u didn't know it?

I need to recheck the parameters; though, NO4 is barely pink on salifert test kit as I recall about 3 weeks ago. I did test for K once, it was very low and replacing it with supplement did not reolve the issue.

i think the issue was low NO4 or some other element that is not tested for. But clearly the problem is now resolved. The mystery persists.

 

[JVJordan]

I've periodically fought the same problem (I think).

I'm still not sure which treatment fixed it, but I believe it was cured by either dosing magnesium (MgS04 / MgCl), Lugol's Iodine (KI?), or potassium nitrate (KNO3). After dosing these three I saw rapid improvements.

Each time it recurs I try to narrow down the cause.

Of course water changes help, but in my experience relief is very brief before the problem begins to worsen again.