Acanthastrea mouth bleaching?

suikerspin

New Member
View Badges
Joined
May 24, 2026
Messages
18
Reaction score
26
Location
netherlands
What state or country do you live in
Other International
Rating - 0%
0   0   0
Hey r2r.

This acan has been in the tank for 2 months now yesterday it was fully puffed up and colors where good.

This morning all the heads are shriveled up and of the heads looks like the mouth is bleaching

Should i be worried it went like this overnight and really havent shown any signs of stress in the last 2 months.



IMG_3774.jpeg

IMG_3773.jpeg

IMG_3772.jpeg

IMG_3771.jpeg
 
I gave it a light blow off and the part that looked bleach just came off was completly dead tissue.



IMG_3776.jpeg

IMG_3775.jpeg
 
I don't see bleaching but the mouth is gaping, I suspect it is hungry, either for nutrients or for light. Can you share your parameters, and type of lighting and flow?
Im feeding ab+ 3 times a week. Its sitting in low-moderate flow zone under a prime hd16 @ around 45% strength

Im running water tests tonight again. But alk was at 8.7, calc around 420, mag around 1320. Nitrate between 15-20 and phos 0.1-0.2 ( phos is really hard to read im expecting the ulr hanna to arive this week)
 
Sorry for the double post, i think the piece that came out of it might have been some of the artemia i feed the fish that got stuck in The head, could this have cause the retraction?

also my skimmer is currently working overdrive for the last 2 hours could this be related?
 
What size is your tank? Any reason to run the light at just 45%?

I have an AI Prime on a 15 gallon softie tank - mostly mushrooms and zoa's - set at 85% for a 10 hour peak period, the tank is 10" deep.

I have the same acan as you under heavy lighting, my acan grew from one polyp to a colony in just 3 years, picture is below.

Your acan is gaping which is a sign of stress, and it seems to me you have your light set too low. I think it needs more light. just my 2 cents good luc



1792422970340.png
 
What size is your tank? Any reason to run the light at just 45%?

I have an AI Prime on a 15 gallon softie tank - mostly mushrooms and zoa's - set at 85% for a 10 hour peak period, the tank is 10" deep.

I have the same acan as you under heavy lighting, my acan grew from one polyp to a colony in just 3 years, picture is below.

Your acan is gaping which is a sign of stress, and it seems to me you have your light set too low. I think it needs more light. just my 2 cents good luc



1792422970340.png

wow that one looks really good! I had it set at 40% and im ramping it up 5% every week, I didnt really had much corals in it in the start, and just slowly have been adding corals the last 2 months so thats why it was so slow.

Should i start ramping it up faster like 10% every week? Tank is a waterbox 25 peninsula
 
Totally agree with @Mr. Mojo Rising , increase the lights now. 45% on a hd16 is barely keeping the coral alive with your tank being 15" height. Honestly, you will probably end up maxing, or close to it, that light out to get adequate PAR on the sandbed.
 
Thats good. Personally I would put it up to about 55% right away, and then start increasing 5% per week until you get to about 75% ish, then re-evaluate how your corals look.
Totally agree with @Mr. Mojo Rising , increase the lights now. 45% on a hd16 is barely keeping the coral alive with your tank being 15" height. Honestly, you will probably end up maxing, or close to it, that light out to get adequate PAR on the sandbed.
Thanks guys i have increased my light to 55% this is now my current Settings which runs from 12:00 till 22:00 with 30 minute ramp up/down

also sounds like i have to start looking at upgrading my light sooner then later 😂



IMG_3780.png
 

TOP 10 Trending Threads

IF YOU WERE CHOOSING YOUR MAIN REEF TANK TODAY, WHAT SIZE WOULD YOU PICK COMPARED WITH YOUR CURRENT

  • Much smaller

    Votes: 1 2.6%
  • A little smaller

    Votes: 0 0.0%
  • About the same

    Votes: 1 2.6%
  • A little larger

    Votes: 14 36.8%
  • Much larger

    Votes: 13 34.2%
  • About the same volume, but different dimensions

    Votes: 4 10.5%
  • I’d keep this one and add a second tank

    Votes: 2 5.3%
  • I don’t have a reef tank yet

    Votes: 0 0.0%
  • Other (Post in the comments)

    Votes: 3 7.9%
Back
Top
Home
Post thread…
Market
What's new