Coraline sudden bleaching

[Djmac]

Hi all,

Just wondering if anyone had any ideas on what might be causing this. This is the third time in a month or so that I've experienced this. Seemingly overnight my coraline algae has bleached out in dots (trochus snail is a good example). Pics taken under whites.

I cant put my finger on any changes apart from starting vodka dosing (2ml in 250L per day, pretty low dose) to try and get some microfauna for the corals to consume (not doing it for nitrate reduction). That doesnt directly line up to seeing these issues and the coraline die off appears to be accute (ie happening all at once on three occasions).

Params:
PH: 8.4
ALK: 7.7 (stable)
Nitrate: 10
PO4: 0.07
Salinity: 1.025
Mag: 1360
Cal: 420

Popbloom RS90 lights at around 60% and running a refugium in sump with reverse photoperiod (growing chaeto like a boss too!).

I'm a bit worried this might be affecting the corals in the tank but its a bit hard to say without a root cause.

 

[ryanjohn1]

To my knowledge that’s just another coralline algae taking over. There are many colors of it

 

[Lavey29]

I agree with the above. Do you have any urchins? Have you checked your par at 60%?

 

[Dburr1014]

Hi all,

Just wondering if anyone had any ideas on what might be causing this. This is the third time in a month or so that I've experienced this. Seemingly overnight my coraline algae has bleached out in dots (trochus snail is a good example). Pics taken under whites.

I cant put my finger on any changes apart from starting vodka dosing (2ml in 250L per day, pretty low dose) to try and get some microfauna for the corals to consume (not doing it for nitrate reduction). That doesnt directly line up to seeing these issues and the coraline die off appears to be accute (ie happening all at once on three occasions).

Params:
PH: 8.4
ALK: 7.7 (stable)
Nitrate: 10
PO4: 0.07
Salinity: 1.025
Mag: 1360
Cal: 420

Popbloom RS90 lights at around 60% and running a refugium in sump with reverse photoperiod (growing chaeto like a boss too!).

I'm a bit worried this might be affecting the corals in the tank but its a bit hard to say without a root cause.

Are you sure about salanity?
How do you test/calibrate??

 

[nuxx]

Should be fine

 

[Djmac]

Salinity - using a cheapie refractometer with 35ppt calibration solution (shaken well) to test its accurate. Its pretty close.

PAR meter, on that rock with the dunkins/acan, about 120-150PAR, bare rock probably around 220par. Measured with a seneye reef. No recent changes to lighting.

A couple of things I missed. I said vodka but i meant vinegar/vodka dosing, using the DIY nopox recipe I found on reef2reef.

I've also added Aquaforest Life Source (reef mud) a within the last few months but havent added any in a few weeks.