PE and Acro health

[Joedubyk]

I consider myself an intermediate SPS keeper in terms of time/knowledge/mistakes, and what I've been able to accomplish, etc.

Since there is so many myths/half-truths about the hobby it's always nice to get the experience from yourself, especially since a good % of people are just parroting stuff online.

I'll say this, it's been said "PE" doesn't matter or isn't a reflection of acropora health. I'm calling BS. After seeing my acros before a tank crash, during a tank crash, and after a recovery -- the healthiest corals are the hairiest. Especially at night . Unless you have an anngel fish or something else disturbing PE during the day, it couldn't be any clearer that hairy acros are healthier acros.

 

[Charlie’s Frags]

Little to no PE has been the first stress signal of every acro I’ve ever lost. I’ve never had stn/rtn just start with good PE. The polyps start to retract for a couple days to a couple weeks before the tissue necrosis starts.

 

[TexasReefer82]

Lack of PE during the day doesn't mean much, ime. I've read that in the wild this is quite normal to protect from polyp nipping fishes... Just like pygmy angels in our tanks. My acros don't have much daytime PE.

But at night they come out! Especially the axial coralites. And big axial coralite PE is also a sign that the Coral is growing.

 

[bmbpka]

I’m by no means an expert in SPS. I have about 10-15 growing well now after many failed attempts. However, I have a copps calacali with no PE. Not once since I put it in my tank. Colors are fantastic. Encrusting the Frag plug with new branches forming. So PE in my experience doesn’t really seem to correlate with health.

 

[danreefman]

I have to see big fat polyps. When you get to where polyps are stretched out everyday, and that's comon, (how I think it should be). If they retract for more than half the day. Than its probably health. If you never have polyps and get good growth and color. I'd say turn down flow, get rid of that fish, or dump some food in.

 

[danreefman]

Or just roll with little to no polyp. My main goal with sticks is to have them waiving like an lps

 

[Macdaddynick1]

IME corals with good PE at night are usually the ones that are actively growing. The corals with little PE at night could be healthy but they’re usually dormant. Overall though I agree,IME good PE usually means a healthier coral.

 

[Joedubyk]

Little to no PE has been the first stress signal of every acro I’ve ever lost. I’ve never had stn/rtn just start with good PE. The polyps start to retract for a couple days to a couple weeks before the tissue necrosis starts.

Exactly. !! Same here. It's a warning sign and you may not pay the price for weeks or perhaps a few months. This is my exact experience as well

 

[Graffiti Spot]

It’s not that it isn’t a reflection of acropora health, it’s just not a reliable measurement of health. Just because polyps are not fluffy doesn’t mean there is an issue. But certain trends with polyp extension could maybe point towards an issue, and can point to nothing as well. I have seen acros actively peel flesh while the other part of the coral has polyps out and is looking beautiful.

 

[ap7x]

I have seen acros actively peel flesh while the other part of the coral has polyps out and is looking beautiful.

Did you ever figure out what caused this for you? I’m sure there’s not one single cause but specifically for your case I mean (or cases).

I had a couple frags from a pack exhibit this.... looking fine, good color, polyps out one day... then next day I wake up to half the tissue peeling while all other parts still have color/polyps. Ended up rtn-ing but still kept polyps out til the end wherever there was tissue. Chalked it up to shipping stress but curious since it seems out of no where. Rest of frags from pack seem fine, other acros fine.

 

[Graffiti Spot]

When that happens after shipping it’s normally just shipping stress/issues. I noticed it when nutrients rose really fast. But peeling like that can be caused by a number of situations I imagine. Ime if an acro has minimal polyp extension, I can normally tell if it is unhappy by seeing if the flesh looks healthy and or if the coloration is right. Using color or things like growth form or the condition of the acros flesh is a better way to tell if an acro is not doing well.

 

[Joedubyk]

It’s not that it isn’t a reflection of acropora health, it’s just not a reliable measurement of health. Just because polyps are not fluffy doesn’t mean there is an issue. But certain trends with polyp extension could maybe point towards an issue, and can point to nothing as well. I have seen acros actively peel flesh while the other part of the coral has polyps out and is looking beautiful.

Agree, and I have seen that too. But throughout my couple years of experience, I can almost definitely say PE can have a direct reflection of acro health. It has been said here and elsewher it doesn't.

 

[Backreefing]

Some acropora just don’t have much for polyp extension . My Cali tort has a little at the trunk nothing at axial polyps. It is happy and baseing out . I just picked up a Hawkins acropora. It was damaged and has healed. But I looked them up and I don’t see any pictures of one with extended polyps. So it must be normal. I have a couple hairy acropora to . Like a orange tip albra , Boomberry acropora. They are always extended .
I think the most important thing is a change or decrease of polyps extended. That probably is a sign of stress. Thx