Coral Dying / Closed

[tim7711]

Hello Fellow Reefers,

I've been battling an issue for 4 days with my coral being closed (detailed below). I'm finding it challenging to why this is happening and more or less have hit a wall trying to find the underlying cause. I've regularly maintained a relatively new tank (~2 months) without major issues other than hair algae and diatoms which my CUC managed well. Lights are on for 8 hours daily. Fish and invertebrates seem unphased at this time. There has been no dosing of nutrients or added chemicals to this tank.

Actions:
Performed a 10G (33%) water change today with the previous 5G gallon change completed on August 28th (part of weekly 5G changes).

Specs:
30G Fish Tank
2 Clownfish
Xenia
4 Colonies of Zoas
Hammer
Duncan
Papaya
GSP

CUC:
6 Hermit Crab
6 Margarita Snails

Parameters:
Temp: 78F
Salinity: 35ppt (using RODI water)
Ammonia: 0
Nitrate: 20
Alk: 10.9
Mg: 1600
Ca: 510
Phos: 0.1 (up from 0.03 Aug 28th, 0.04 Aug 22nd)
* parameters have been relatively consistent for 2+ weeks unless stated otherwise

 

[blaxsun]

Can you post any images?

 

[Jekyl]

Also how old is the tank, and what lights/schedule is being used?

 

[Uncle99]

MG high. Target 1365-1420ppm, 1600 may slow or kill you snails.
Others look good, how long travel they been like that?
2 weeks?
I was thinking more like 2 months for the system to take on even softies.
Corals die in early tanks as the bacteria necessary to feed them is not at sufficient populations for some time.
The longer it matures, the easier they are to keep.

 

[Jekyl]

MG high. Target 1365-1420ppm, 1600 may slow or kill you snails.
Others look good, how long travel they been like that?

You know I skimmed over this... OP are you using calibration liquid to ensure getting a correct salinity measurement? Not sure any salts mix that high is why I ask.

 

[tim7711]

Can you post any images?

Yes! Can post pictures tomorrow

You know I skimmed over this... OP are you using calibration liquid to ensure getting a correct salinity measurement? Not sure any salts mix that high is why I ask.

I use Reef crystals by Instant Ocean. Yes, the refractometer has been calibrated. Thanks for the insight regarding levels of magnesium. Just for clarification, the levels of magnesium have been persistently elevated since July 23rd. All the corals have suddenly closed up over the past 4 days. What could cause the acute change?

Also how old is the tank, and what lights/schedule is being used?

2 months. 8-10 hours of light

 

[Jekyl]

Yes! Can post pictures tomorrow


I use Reef crystals by Instant Ocean. Yes, the refractometer has been calibrated. Thanks for the insight regarding levels of magnesium. Just for clarification, the levels of magnesium have been persistently elevated since July 23rd. All the corals have suddenly closed up over the past 4 days. What could cause the acute change?


2 months. 8-10 hours of light

Reef crystals should only be mixing to 1440 mag. Not using saltwater for top off right?(it's happened before) As for your refractometer the liquid you have is fluid that you purchased or made and not just RODI? What lights do you have?

 

[tim7711]

Reef crystals should only be mixing to 1440 mag. Not using saltwater for top off right?(it's happened before) As for your refractometer the liquid you have is fluid that you purchased or made and not just RODI? What lights do you have?

Good thought! Yes, I'm using RODI water to top off not saltwater. I used BRS refracto juice to calibrate the refractometer

 

[Goby Bryant]

We need white light pics.