Is this rock coral dead/dying?

loneboat · Jun 10, 2021

I bought this guy a couple of months ago. He's acted/looked happy since then, and settled in that one spot and hasn't moved from it. I thought he was doing fine, but this week he looks "weird". The tentacles are all shriveled looking, and the mouth is constantly gaping open (instead of opening only when I feed him). Also I put some shrimp on him, and instead if the usual disc-contracts-and-mouth-opens, it kind of just sits there.

My levels all seem normal (ammonia/nitrate/nitrite/ph/salinity). I'm wondering if temps have started swinging at night as it's been getting warmer (this is in an office building where I don't control the temperature). I have temp-controlled fans and an ATO, and I haven't noticed a spike in evaporation though.

Also, I have 3 fish, a couple of other corals, some crabs, etc, and everyone else seems happy and is acting normally.

T-J · Jun 11, 2021

FYI, nems aren't corals.

When nems aren't sticky (grabbing food) it's because they are stressed. What exactly are your water parameters? What is the tank temperature? How old is the tank? What light are you using?

loneboat · Jun 11, 2021

Doh, dunno why I typed "coral" ;Facepalm

Just checked all my levels:

Temp	79.07 F
Salinity	1.025
Ammonia (ppm)	0.125
Nitrite (ppm)	0
Nitrate (ppm)	2
pH	8.1
Phosphate (ppm)	0.25
Copper (ppm)	0

T-J · Jun 11, 2021

loneboat said:
Doh, dunno why I typed "coral" ;Facepalm

Just checked all my levels:

Temp 79.07 F
Salinity 1.025
Ammonia (ppm) 0.125
Nitrite (ppm) 0
Nitrate (ppm) 2
pH 8.1
Phosphate (ppm) 0.25
Copper (ppm) 0

Assuming these are accurate (API tests are some of the worst out there), Ammonia should be zero (could be the API test) and Phosphates are pretty high. High phosphates wouldn't bother the nem tho (they usually like higher PO4 and Nitrates).

What about your lighting and flow?

loneboat · Jun 11, 2021

Oh right: I'm using a 32G Biocube (newer one - I think I heard somewhere there were some changes to it in the last few years), with stock lighting, which I've heard isn't great. However, I have some algae growing on the sides (have to scrape it every other week or so), so I figured that was indicator that the lighting's at least decent.

For flow, I've added one of these guys: , which claims 1600gph. I have it on a pulse mode, so it varies between 0% and 50% power every 10 seconds or so. The nem settled into that spot on day-1 a few months ago, and has seemed happy since. I figured that meant it was happy with what it was getting.

loneboat · Jun 11, 2021

(by the way, I'm somewhat of a noob to this, so I appreciate any and all info/pointers! Thanks for taking the time to reply!)

T-J · Jun 11, 2021

loneboat said:
Oh right: I'm using a 32G Biocube (newer one - I think I heard somewhere there were some changes to it in the last few years), with stock lighting, which I've heard isn't great. However, I have some algae growing on the sides (have to scrape it every other week or so), so I figured that was indicator that the lighting's at least decent.

I've never owned a Biocube, but when I see people using them, they usually scrap the stock light. Maybe someone can chime in on the light, as I'm unfamiliar with it. Having said that, I'd be pretty shocked if it was giving off sufficient PAR.