Polyp Extension Question

[Scubabum]

Hello everybody. Long time reefer but fairly new to keeping SPS. My tank is a Red Sea Reefer 525XL. My Parameters are SUPER Stable at 7.5 DKH, 440 Cal, 1400 Mg, Nitrate 5-8ppm and Phos .04-.06. I'm getting good growth and have great color on all my SPS. I've noticed that I have very little polyp extension during the day. At night the polyps are out in full force. If I add a new frag, the polyps are out for a few days and slowly retract during the day but are out at night. Only thing I can think of is I have a Flame Angel in the tank. I have watched it for countless hours and even setup a camera to keep an eye on the Flame Angel. I do see the Flame picking every once in a while but also picks on the rock the same way. Not seeing any type of flesh damage. Not sure if the Flame is irritating the coral or actually eating polyps. Thoughts???? Thanks in advance.

 

[laverda]

I have a similar situation in my 300 gallon. I have a charib angel, a lemon peal angel and a bicolor angel. I have never seen any of them pick at the corals. Infact they spend most of their time lower in the tank then where my SPS are. A fellow hobbyists told me just having the angels in the tank was enough to cause them to not extend their polyps. I have no idea if that is true or not.

 

[jda]

PE does not matter. PE can be both a good sign, or a bad. What you really want to look for is changes - good PE corals suddenly without any or bad PE corals suddenly with some. I would expect something like a Walt Disney Tenius to have a lot of PE, or I would worry. I would not expect most smooth skinned acros to have any, or else I would worry that they are having trouble respirating (not enough oxygen (carbon dosing can do this), too high of ammonia, etc).

Most PE is for gas exchange. They are out more at night since there is no light and photosynthesis to supply gas to the coral. Veron always used to say that a happy and healthy coral that needs nothing will not risk getting their polyps eaten.

Most dwarf angels pick some. Even though most pick a bit, not many do any (or enough) damage to worry about anything. Some can be holy terrors, but you would be seeing them rip flesh off of acros if you had a bad one.

 

[Scubabum]

PE does not matter. PE can be both a good sign, or a bad. What you really want to look for is changes - good PE corals suddenly without any or bad PE corals suddenly with some. I would expect something like a Walt Disney Tenius to have a lot of PE, or I would worry. I would not expect most smooth skinned acros to have any, or else I would worry that they are having trouble respirating (not enough oxygen (carbon dosing can do this), too high of ammonia, etc).

Most PE is for gas exchange. They are out more at night since there is no light and photosynthesis to supply gas to the coral. Veron always used to say that a happy and healthy coral that needs nothing will not risk getting their polyps eaten.

Most dwarf angels pick some. Even though most pick a bit, not many do any (or enough) damage to worry about anything. Some can be holy terrors, but you would be seeing them rip flesh off of acros if you had a bad one.

I added a Walt Disney Tenius 2 weeks ago. They polyps were really extended for about a week. They are still out but slightly retracted. This seems to be the case with any coral I add. Again I'm still getting growth and great color so I'm pretty sure its not a water quality issue. Hopefully they are happy and healthy and not risking their polyps getting eaten. I'm sure my corals are fine but they just look so much better with polyps extended. Thanks for the reply.

 

[jda]

Go with growth and color before PE as an indicator. PE does not mean nothing... it is just impossible to know what it means... kinda like mantle extension in Clams where too much can be a good or bad thing.