Why is my acro bleaching?

[Koty]

I have a 100g tank not aimed at SPS as I do no water changes and have many fish fed a lot. This Acropora started from a frag of Xenia that died, and the acro grew from nothing. Now it started bleaching, and I am trying to think how to stop it.
The reason/s may be the following:
1. An overdosed trace element (I constantly dose TM A and K elements )
2. A missing trace element (Chaeto started growing like crazy with the TM A and K elements)
3. Flow issues (I have a Maxspect gyre wave maker, and they lose power from stuff growing on them.
Parameters are very stable: KH 8.8±0.1, PO4 0.2 ± 0.04 NO3 12 ±5
I have put a Metazorb bag for three days to reset the trace elements.
I also thoroughly cleaned the gyre in citric acid and dishwasher soap.
I suspect it's the flow, as other SPS corals are doing fine.
Any other suggestions?

 

[Macdaddynick1]

I’ve killed off an entire tank of 100s acros with overdosing K. They looked just like your acro. Started one by one and then all went to white. I would stop. Just start doing water changes, safest, most simple method that will achieve the same result with 1/4 the hassle.

This statement makes me believe you’re doing too much : “ I have put a Metazorb bag for three days to reset the trace elements” just go back to the basics.

PS I doubt you can do anything for this acro at this point. If it goes it goes, so don’t do any drastic changes, It will more likely mess with the corals that look good then help the dying one.

 

[Koty]

Tanks, by o"verdosing K" do you mean Potasium or the TM K-element mix?
My Potasium has been around 400-430

 

[Macdaddynick1]

Tanks, by o"verdosing K" do you mean Potasium or the TM K-element mix?
My Potasium has been around 400-430

Overdosing potassium, mine was lower than that, it’s the dose I added at once what did it.

 

[Epic Aquaculture]

That does not appear to be bleaching. it looks like necrosis which is much worse. Are you sending ICP tests to monitor your trace elements? I would suggest a series of large water changes over the course of a week. Adding Metazorb will not reset your trace elements. It sounds like you're doing too much at once. Too many changes are just as, or even more stressful than doing nothing...

 

[Koty]

Thanks. I have not added potasium in a while. Besides metasorb and clean the wavemaker i have not done any changes.
Why do you say metazorb does not reset trace elements? Can you elaborate?
It is dying very rapidly so it looks from bacterial source. All other corals are doing fine.
I have not done ICP. But i do not have an indication of a "global" effect other sps corals.

 

[Koty]

Adding Metazorb will not reset your trace elements.

Yes indeed, only Cobalt Iron Copper Manganese Nickel Zinc and Selenium are adsorbed from what I supplement, and Strontium Bromine Fluorine Iodine Lithium Molybdenum Barium Boron Chrome and Vanadium are not.

 

[Koty]

What bugs me is that other corals in the tank look apparently happy (the ones that don't the CBB is the culprit).

 

[billyocean]

Could have been lack of flow or overdosing. At the end of the day acros can die out of the blue sometimes..so there's that factor also. How old is the tank? It looks like everything else is happy so like others have said...don't chase one coral. Just be vigilant for others displaying issues

 

[Koty]

The tank is 2y8m old. My guess is an opportunistic bacterial infection due to bacterial overload, meaning that the water may have got a bit too dirty. I have a UV but have a slow flow through it to sterilize the water going through it. Maybe need to change the filter wool more often. Also, I am very curious as to what an ICP will show after close to 2 years w/o a water change.

 

[Max93]

Have you tried sending out another ICP test? I notice people lose a lot more coral in the warm seasons due to their city water adding more chemicals to reduce algae blooms in the water. Your RODI should be the first thing you check - 0 TDS doesn’t mean you are catching everything.

 

[Pistondog]

With necrosis, i ended up fragging off the healthy parts aand tossing the bad.

 

[Koty]

Have you tried sending out another ICP test? I notice people lose a lot more coral in the warm seasons due to their city water adding more chemicals to reduce algae blooms in the water. Your RODI should be the first thing you check - 0 TDS doesn’t mean you are catching everything.

The ICP test is coming soon. As all other corals are fine, I doubt that water is an issue. Water in Israel is very dirty and hard all year round. I run two resin columns after the RO filter. I read somewhere that temperature is an issue more for LPS that came from Australia where the water is a bit colder. My max temp is 25 ± 1 °C.

 

[Koty]

With necrosis, i ended up fragging off the healthy parts aand tossing the bad.

Too late. He is gone