Is this STN?

[livinlifeinBKK]

I've had this tenuis for about a week and a half now and it has seemed to be doing fine but I was gone for a couple days on a trip and now it looks like it's either bleached a little while I was gone or maybe STN...nitrate about 5 phosphate around .05-.1 (hard to color match perfectly with Salifert...my alk hangs around 9...I noticed my chiller hose had a kink in it which may have been stopping the water from going through the chiller and caused it to heat up a little too much so maybe that's it...this is my first tenuis so idk how to diagnose these issues properly

 

[livinlifeinBKK]

Bump

 

[ScottB]

Does look like base recession. Do you have other happy acros in there long term?

 

[livinlifeinBKK]

Does look like base recession. Do you have other happy acros in there long term?

No, this is my first which is why I'm trying to get on top of it asap...I actually reposted this after I hadn't received any replies after a couple hours because I really want my first tenuis to do well

 

[ScottB]

No, this is my first which is why I'm trying to get on top of it asap...I actually reposted this after I hadn't received any replies after a couple hours because I really want my first tenuis to do well

Acros are the least robust of all corals we try to keep in captivity. They require MANY things to be just right.

Age of system?
Dead or live rock start?
alkalinity?
Nitrate level?
Phosphate level?
How many fish and how many gallons?

 

[livinlifeinBKK]

Age~several months
Live rock fresh from the ocean
Alk =10.5
Nitrate~5
Phosphate~.05-.1 (hard to tell with Salifert
No fish, coral/ invert only...10 gallon nano
@ScottB I spent months strengthening and diversifying my microbiome in many ways before trying any SPS corals, especially this one.

 

[LOVEROCK]

What temperature did tank hit ? The highest

 

[livinlifeinBKK]

What temperature did tank hit ? The highest

Not sure because as soon as I got back I saw the chiller hose was kinked and right away unkinked it...I didn't look at the temp but I think since the tissue loss starts at the base it's more likely due to an alk swing or something like that...I do test alk every 2 or 3 days and don't see how it could've swung more than 1 DKH or so though

 

[ScottB]

Age~several months
Live rock fresh from the ocean
Alk =10.5
Nitrate~5
Phosphate~.05-.1 (hard to tell with Salifert
No fish, coral/ invert only...10 gallon nano
@ScottB I spent months strengthening and diversifying my microbiome in many ways before trying any SPS corals, especially this one.

I applaud the use of live rock. Nutrient levels look OK (although you need Hanna ULR for PO4). ALK might be a tad high depending on what those frags grew up in. All my sources grow in 8ish dkh.

Personally, I have never seen a sustained acropora reef without fish -- captive or otherwise. I have asked here hundreds of times. It seems that this is an immensely difficult thing to do over time.

In theory, you should be able to replace the continuous secretion of ammonia that the fish provide to the corals; I am just not sure what that looks like.