Struggling to get Acropora Polyp Extension (1 Viewer)

[oguzman]

Hi all,

I'd like to pose a quick question why do my Acropora not extend their polyps during the day light cycle? On a side note they are encrusting and growing ... I unfortunately ONLY get extension during the night but nothing when the lights are on.

I am running the following:
75g tank with a 29g fuge (id Say about 15g of water) with a 16 gallon frag tank hooked up to the system for the added water volume.
SCA 302 Skimmer
Refugium with Chaeto and a Par38 15 hour cycle
Mp40 Running at about 60-70% power Mp10 Running at 100% in Ecotech Mode
Lighting is 2X Kessil A360WE at 75% for 8 hours with a 2 hour ramp up and ramp down cycle AND
1X ATI blue plus and Aquablue Special for 6 hours
Run Carbon and GFO at half dosage recommended by BRS
I'm using Red Sea Salt (I increase the Mg before I place it in the tank to about 1300ppm)

I also dose kalk using the two little fishes kalk stirrer (.25 cups/2 weeks)
I also dose the KZ line: K Balance, B Balance, Sponge Power, Flatworm Stop and finally Coral Vitalizer
Reef Energy A and B daily ...
I feed my fish daily as well

My water parameters are as followed:
Nitrate usually around .25ppm to .5ppm
PO4 I really cant tell it looks like its zero
Alk 9.3
Ca 420-440
Mg 1300
Sg 1.025
Temp 78F

 

[flipside]

How old is your tank?

To be honest, polyp extension is not the signs of a healthy acro. It actually means that it's hungry. Seeing a lot of polyp extension (PE) is a common thing with low nutrient systems, and for those of us that do feed the corals. If your colors look good, encrustation is strong, and growth is prevalent, you really have nothing to worry about.

Another thing you could try, if you trust your system is stable enough, is to try cutting off the GFO, carbon, and skimmer for a day or two. You might be surprised.

On a side note, I like the way you have your system setup. I would probably add 2 more T5's, but that just me.

Good luck!

 

[Wingnut]

Have you tried lowering your Alk. , everything I have read and see in my tank with low nutrients 9.3 Alk. Could be a little high my No3 is around 2 Po4 .03 and I try and keep Alk. 7.8 to 8.0. Just a thought

 

[oguzman]

I'll try both suggestions. I spoke with Reefling earlier this week and he mentioned the exact same thing btw flipside. In that case I would have to lower the nutrients even more which could be bad news for LPS and softies ... ugg mixed reefs ...

 

[PSXerholic]

Hi all,

I'd like to pose a quick question why do my Acropora not extend their polyps during the day light cycle? On a side note they are encrusting and growing ... I unfortunately ONLY get extension during the night but nothing when the lights are on.

I am running the following:
75g tank with a 29g fuge (id Say about 15g of water) with a 16 gallon frag tank hooked up to the system for the added water volume.
SCA 302 Skimmer
Refugium with Chaeto and a Par38 15 hour cycle
Mp40 Running at about 60-70% power Mp10 Running at 100% in Ecotech Mode
Lighting is 2X Kessil A360WE at 75% for 8 hours with a 2 hour ramp up and ramp down cycle AND
1X ATI blue plus and Aquablue Special for 6 hours
Run Carbon and GFO at half dosage recommended by BRS
I'm using Red Sea Salt (I increase the Mg before I place it in the tank to about 1300ppm)

I also dose kalk using the two little fishes kalk stirrer (.25 cups/2 weeks)
I also dose the KZ line: K Balance, B Balance, Sponge Power, Flatworm Stop and finally Coral Vitalizer
Reef Energy A and B daily ...
I feed my fish daily as well

My water parameters are as followed:
Nitrate usually around .25ppm to .5ppm
PO4 I really cant tell it looks like its zero
Alk 9.3
Ca 420-440
Mg 1300
Sg 1.025
Temp 78F

Let me poke first ;-)

Look at this Polyp extension first....................

[video=youtube;rdFJDCBeKR4]https://www.youtube.com/watch?v=rdFJDCBeKR4[/video]

-Andre

 

[PSXerholic]

Let me poke first ;-)

Look at this Polyp extension first....................

[video=youtube;rdFJDCBeKR4]https://www.youtube.com/watch?v=rdFJDCBeKR4[/video]

-Andre

Best is to start dosing nutrients and support in addition with a large but very gentle flow pattern. Ideally from Wave makers.
For Nutrient increase, I just released an e-publication (Andre's Reef Guide) for tank issues with low nutrients to get colors back up.

Cheers,
Andre