Help !! Corals rapidly getting more upset

[imbob95]

My tank seems like it’s being nuked by something just based on how quickly things are declining…

Parameters
Nitrates 0ppm
Phosphates 0.25ppm
KH 9dkh
Calcium 400 mg/L
Salinity 1.026
Temp 80F

Crew
Six line wrasse
Watchman goby and pistol shrimp
Emerald and pom Pom crab
Various snails/hermits - some of the snails have started to detach today

Some background: we have 6 month old (seeded with live rock from an existing system that was up for about a year and a half) 13.5 fluval evo that was thriving before we went on a 3 week vacation. We had been feeding mysis shrimp but then had an auto feeder feeding dry food. Had a tank cam to watch while we were away and everything was fine other than a little algae growth but nothing drastic.

Came back from vacation and starting feeding mysis shrimp again.

We’ve been back around a week and things were looking good until the last few days - things have just not been looking good

Xenia: the Xenia has been shrinking, turning white, and now appears to be releasing slime

Kenya tree: the Kenya tree has looked a little spotty for a while, as though the tips are bleached? But it continues to reach for the light

Zoas: they were looking mainly fine but today have just really closed up

Mushrooms: shrivelling up and potentially releasing a bit of mucous

I know the nitrates are too low so have fed a little more today and put some reef roids in there but this all seems a bit dramatic for low nutrients, especially because it seemed fine while we were away.

Could the Xenia dying and emitting the slime be nuking the tank? I can’t imagine it would but everything has so rapidly declined

Currently preparing water for a water change and so we can siphon out some of the slime

 

[Cichlid Dad]

Possible your nutrients. Bottomed out nitrates and higher phosphate.

 

[Mr. Mojo Rising]

looks like the tank needs more flow. The water surface is completely flat so low oxygen exchange between water and air. It also looks like some corals are reaching up to the light, turn the lights up if you can. Corals will thrive if you give them light flow and nutrients, these are the 3 magic ingredients.

I would add a small powerhead in there and aim it at the surface to agitate the surface and create more flow in the tank.

Are you using API for the phosphate test? If yes, then throw it out. We need to know the exact measurement, but API only provides a range from zero to .25, this is not accurate enough. API tests are generally frowned, use salifert instead.

 

[Kooma]

I would also start running some activated carbon in a bag in the filter in case something is releasing a toxin.