Full polyp expansion on monti's but not acro's, WHY?

[Acronuts1]

Hello all,

I need your help! I need to know why when I place a new acro, the polyps are fully expanded. Then within a few days they retract to where I can only see the tips.

My monti's and pocilliporas are out in full glory.

I am getting growth from all.

My parimeters are all fine:

ph 8.4

ca 460

alk 14 a bit high

mg 1200 to 1400

phos 0 according to test kit

nitrate is around 10-20, drops down with water changes every two weeks at 15%

no

nitrites, ammonia

I do have a flameback pigmy angel but have never seen it peck at the sps's.

Help please or am I just crazy?

 

[Anonymous]

Chemical warfare of the corals? I donno, but I feel that if you see no issue with the acros, you just have to have more patience. Some of us are too much into this size/entension/epansion thing too much, you know.

 

[Ben1]

Have you looked at them at night with a flash light to see if they are extending their polyps then?

 

[Anonymous]

Chemical warfare of the corals? I donno, but I feel that if you see no issue with the acros, you just have to have more patience. Some of us are too much into this size/entension/epansion thing too much, you know.

 

[Acronuts1]

Last night I looked at the sps's and saw the polyps fully extended!
All were out except for one milliepora, it sits toward the back and I really could not see full PE only partial.
So now what does this say?

 

[Ben1]

IME that indicates fish nipping. If it was just a few I would say normal. as some acros just do this. If it is all the acros on the tan k and you have many then I would think its a nipping fish.

 

[leftovers]

Not seeing polyp extension during day time is normal and nothing to be alarmed about. Most corals do not extend polyps during the day as they say "eat me" to fish.

They do normally extend at night when they feed. Most corals do their primary feeding via plankton at night via their polyps extending out into the water column.

You will also see stringers out at night....wait about 1hr or so after its dark and use a red light on the tank to see. Bright white lights can be hard on the fish and can spook them...and they can and do stupid things...

 

[Anonymous]

So now what does this say?

If you got these corals as wild-caught specimens, then I bet it is due to jet lag.... :wink:
<run away>

 

[Anonymous]

My acros only open at night as well, but they are growing well. My Stylo, pocillipora, and montis are extended day and night.

 

[Acronuts1]

This does make you think, doesn't it.
I will keep an eye on things and for now as long as they are growing I won't mind the lack of full pe during the day.
Besides my monti's and pocilliporas are out day & night.
What type's of food do you guys feed at night?

 

[leftovers]

This does make you think, doesn't it.
I will keep an eye on things and for now as long as they are growing I won't mind the lack of full pe during the day.
Besides my monti's and pocilliporas are out day & night.
What type's of food do you guys feed at night?

Not at all, there is little need to feed your corals directly. They will, under most conditions get plenty of food from the water column and lights, and when you feed your tank they will usually tend to extend to partake to some degree.

Again, corals in the wild dont extend their tentacles till after the sun goes down anyways.

 

[Anonymous]

I rarely feed them but if I do I feed plankton in selcon via turkey baster.