Acropora not showing polyps

Jack McManus · Aug 22, 2018

Is there a reason my acro isnt extending its polyps? It did go through a phase of stn a few months ago but has actually made quite the comeback (I believe it went downhill because of low alk and calcium). I see it extend what I believe are "feeding tentacles" at night. My other sps always have their polyps out. The acro hasn't quite completely covered all of its old skeleton but there is a fair amount of new growth.

Parameters as of a couple hours ago are:
Salinity: 1.024
Temp: 78
Alk: 9.3
Calcium: 450ppm
Nitrate: 0.5ppm (I've been trying to raise this as it was 0.0 for a few weeks)
Phosphate: 0.04ppm

Reefpuck · Aug 22, 2018

Angel nipping at them? My flame likes to nip at some pieces...while leaving others alone.

Jack McManus · Aug 22, 2018

It's a possibility butI haven't seen my cherub angel pick at anything other than algae on the glass and rocks

Reefpuck · Aug 22, 2018

Cherubs are actually one of my favorite... and yet the reason I don't own one is they're typically more prone to nipping than a flame or coral beauty. At least that's my experience.

DMG Reef · Aug 22, 2018

I recommend raising your salinity to at least 1.025 and preferably 1.026 for corals. Your alk is a little high also considering your nutrients are low. An alk reading of 8.0 would be better tolerated by SPS.

As for the polyps, don't worry too much about that. Some acros have great polyp extension while others have very little. As long as it's growing, that's what matters. Good luck.

Jack McManus · Aug 22, 2018

Thank you for your input. I'll implement these asap and see how things go and I definitely agree, growth is what really matters

Alfrareef · Aug 23, 2018

And what about flow. What pumps are you using and what’s tank size?
Post a FTS?

coral-boss · Aug 23, 2018

i had a similar problem with my acros until I added another wavemaker and they seem to be much happier and show extension all the time now. but I have to agree with @Kattkrazie as long as they are growing I wouldn't focus on them not having extension.

beardown · Aug 23, 2018

Kattkrazie said:
I recommend raising your salinity to at least 1.025 and preferably 1.026 for corals. Your alk is a little high also considering your nutrients are low. An alk reading of 8.0 would be better tolerated by SPS.

As for the polyps, don't worry too much about that. Some acros have great polyp extension while others have very little. As long as it's growing, that's what matters. Good luck.

I'll agree with the salinity, but the Alk I do not. There's an ebb and flow with a tank. My alk is currently at 11.2, and I have nice polyp extension on all my sps. I don't fight my water. I keep it stable at 11.2-11.3 and I don't have any consequences, so long as I keep my calc/mg levels correct.

ca1ore · Aug 23, 2018

Agree that as long as they are growing, nothing to worry about. FWIW, I have acros in my main display as well as in my frag tank. It's a connected system, with conditions as close as I can make them - acros in the frag tank show much more PE on average than those in the display. The difference: no finned nippers in the frag tank!

DMG Reef · Aug 23, 2018

beardown said:
I'll agree with the salinity, but the Alk I do not. There's an ebb and flow with a tank. My alk is currently at 11.2, and I have nice polyp extension on all my sps. I don't fight my water. I keep it stable at 11.2-11.3 and I don't have any consequences, so long as I keep my calc/mg levels correct.

Different parameters work for different people. However, a new reefer who has stripped the nutrients from his tank and has an SPS that has STN and is recovering should probably take a look at his alk levels. High alk is fine for experienced reefers but can create problems for hobbyists who are just starting out.

Huskymaniac · Aug 23, 2018

I will just add stability is key. I have always had something bleach on my me when I make changes. The more changes you make the worse things will be.

reeferfoxx · Aug 23, 2018

Reefpuck said:
Cherubs are actually one of my favorite... and yet the reason I don't own one is they're typically more prone to nipping than a flame or coral beauty. At least that's my experience.

I actually bought a Cherub over 2 years ago just because they were widely known to be the least likely to nip. So far, my cherub hasn't bothered anything.

reeferfoxx · Aug 23, 2018

Alfrareef said:
And what about flow. What pumps are you using and what’s tank size?
Post a FTS?

My vote is for flow and possibly low nitrates.

Reefpuck · Aug 23, 2018

reeferfoxx said:
I actually bought a Cherub over 2 years ago just because they were widely known to be the least likely to nip. So far, my cherub hasn't bothered anything.

Feedback is always based on experience...and with any angel it can go both ways. Hit or miss....but just my experience reading the forums.

reeferfoxx · Aug 23, 2018

Reefpuck said:
Feedback is always based on experience...and with any angel it can go both ways. Hit or miss....but just my experience reading the forums.

Definitely hit or miss. Cherubs for the most part lean more towards being herbavores though omnivores. A well fed cherub with it's own space will least likely bother coral. Just my experience.

vetteguy53081 · Aug 23, 2018

Medium light intensity, Feed 2X per week, Moderate to Medium flow and Amino acids.
I also add potassium, iodide, stronium, and Trace elements daily at low amount