How important is polyp extension? What do you do to get it? What steps do you take if you don't?

[Daniel@R2R]

How important do you think polyp extension is as an indicator of coral health?

What have you found to help promote PE?

What steps do you take if you notice you're not getting the PE you want in your corals?

Hoping this will be a great discussion!

Photo by @TopShelfAquatics

 

[Reefahholic]

I believe it’s very important.

If you’re not getting decent PE I think the first thing to consider is that some Acro’s just don’t have much PE to begin with. Others may not have much PE initially, but once they settle in, and become happy they develop some very nice PE that will shock you later.


There’s 4 factors I focus on in my tank that I feel are directly related to PE. If you can get these right (or close to right) then good PE will naturally follow. Here’s my .02 cents:

1. Chemistry- Dial in chemistry as much as possible. If some corals are lacking a few trace elements it can definitely affect PE.

2. Weak Flow- I’ve been a victim! Sometimes I feel like we think we have enough flow, but we really don’t. I have 6 Wave-Makers in a 105/G. 2x Nero 5’s, 2x Nero 3’s, 2x Jebao MLW 30’s. I feel like I could use 2 more. Acro’s can handle a ton of flow as long as it’s indirect and random. With all these Wave-Markers I have two corals that get perfect random flow that have a 50% higher growth rate on the sides that get blasted the most. Shockingly there’s still a lot of dead spots in the tank. I think strong random flow is very important for good PE.

3. Light- We know corals can adapt to many different PAR ranges. What they can’t adapt to is constant tinkering! Setup the lights, dial them in with a PAR meter and leave them alone. I can tell you that it’s very easy to play with LED channels and intensities.

4. Nutrients- This is tied in with chemistry, but can make or break a system. So for me NO3/PO4 need to be treated separately and require special attention (especially PO4). I’ve seen low or depleted PO4 completely affect PE. This is obviously different for every system and changes as the tank matures, but if you had a PO4 level of say .08 ppm, and then you notice 3 days later that PE is completely gone, it may be a good idea to check PO4 preferable with a Hanna ULR. If it tests at .01 ppm or zero then you have most likely found your problem. NO3 seems to be much less important, but if it sits a zero for too long it will lead to issues down the road. Don’t believe me, look at the pic below of my wife’s tank from about 3 years ago.

 

[Daniel@R2R]

I believe it’s very important.

If you’re not getting decent PE I think the first thing to consider is that some Acro’s just don’t have much PE to begin with. Others may not have much PE initially, but once they settle in, and become happy they develop some very nice PE that will shock you later.


There’s 4 factors I focus on in my tank that I feel are directly related to PE. If you can get these right (or close to right) then good PE will naturally follow. Here’s my .02 cents:

1. Chemistry- Dial in chemistry as much as possible. If some corals are lacking a few trace elements it can definitely affect PE.

2. Weak Flow- I’ve been a victim! Sometimes I feel like we think we have enough flow, but we really don’t. I have 6 Wave-Makers in a 105/G. 2x Nero 5’s, 2x Nero 3’s, 2x Jebao MLW 30’s. I feel like I could use 2 more. Acro’s can handle a ton of flow as long as it’s indirect and random. With all these Wave-Markers I have two corals that get perfect random flow that have a 50% higher growth rate on the sides that get blasted the most. Shockingly there’s still a lot of dead spots in the tank. I think strong random flow is very important for good PE.

3. Light- We know corals can adapt to many different PAR ranges. What they can’t adapt to is constant tinkering! Setup the lights, dial them in with a PAR meter and leave them alone. I can tell you that it’s very easy to play with LED channels and intensities.

4. Nutrients- This is tied in with chemistry, but can make or break a system. So for me NO3/PO4 need to be treated separately and require special attention (especially PO4). I’ve seen low or depleted PO4 completely affect PE. This is obviously different for every system and changes as the tank matures, but if you had a PO4 level of say .08 ppm, and then you notice 3 days later that PE is completely gone, it may be a good idea to check PO4 preferable with a Hanna ULR. If it tests at .01 ppm or zero then you have most likely found your problem. NO3 seems to be much less important, but if it sits a zero for too long it will lead to issues down the road. Don’t believe me, look at the pic below of my wife’s tank from about 3 years ago.

This is a really helpful response. I think many people automatically assume chemistry or nutrients when it may be something like a flow issue. I agree that flow is an essential part of coral health and one that I think many of us may overlook in these conversations.

 

[Reefer Matt]

I find along with proper water chemistry, lighting and flow are linked to polyp extension, and higher par levels require higher flow. I believe lighting and flow should match for best PE and coloration. I also find I can make lps have huge polyps by decreasing light and flow, but keeping nutrients higher. It's a balancing act, but does have some margin of error.

 

[shakacuz]

stable water parameters and good flow will get good PE. personally, i don’t chase it and just allow it to occur naturally. if i see lots of it i try to maintain the environment the same so it can continue

 

[Randy Holmes-Farley]

I think the flow issue is coral dependent.

When I had clone bubble corals (Plerogyra sinuosa) in both my refugium and my main tank, the ones in the refugium with hardly any flow had far greater polyp (bubble expansion) than those in the main tank.

 

[Minifoot77]

I have some with and some with out so just here to gather information

 

[Susan Edwards]

I don't consider myself a newbie anymore but still young and learning! My current tank of just over a year (upgraded) astounds me with my coral growth including PE. I have a tenius that is positively fuzzy and some acros that browned when new and have come back with great PE and return of color and new growth. I love, at night, to take my blue flashlight and go spy on the corals and see who is out at night but not during day and make sure those out in daytime are still out at night. I have 3-4 corals I use to gauge things.

I think lights play a big part but agree that flow seems to be the big difference. I had 4 powerheads in the last tank and yet had horrible flow and corals struggling. This tank, 2 gyres and 2 mp40's and I attribute my so far success on having enough flow. Eventually I want to add 2 more mp40's.

I also find in this tank, no3 and po4 are much more stable even though it goes up and down. Right now I have another bout of algae--bryopsis again I think (3rd time) and zero no3 and po4 (last time I tested) Yet all looks fantastic (I believe the algae is consuming my no3 and po4). Will be adding reef flux in a day or 2.

One of the greatest joys is seeing happy corals!

recovering tyree Pinky the bear

Tenius

Yellow Tip Tort

Oregon Blue Tort finally showing growth and PE

 

[tbrown]

How important do you think polyp extension is as an indicator of coral health?

What have you found to help promote PE?

What steps do you take if you notice you're not getting the PE you want in your corals?

Hoping this will be a great discussion!

Photo by @TopShelfAquatics

I've recently added a couple of Acropora to my tank. Lots of flow is what I was told - people recommend putting them directly in front of the powerhead. Today I moved the rack they were on to an area with a little less flow but way more random and their PE was significantly increased. Random heavy flow, stable parameters, and amino acids.

 

[Rams]

Flow,lighting,stability that’s it.Plain and simple for acros

 

[Larry Stewart]

I am learning that PE is a rather important event - I see it as a way that corals receive from the water column. Feeding, receiving and releasing....

I typically notice more PE and open mouths from my corals when the lights are off in the system (after 10pm).

However, prior to having polyp extension and open mouths in the dark I experienced the same behaviors during the daytime which is due to consistent nutrient control, increased waterflow, lighting and the addition of trace elements for coloration/growth. I am now dosing amino acids.....just started 1 hour ago using a Versa dosing pump and the TLF AcroPower. I feel like automation timed correctly help save my reef.

My PO4 at one point were hovering around 2.7 ppm....and NO3 of 20ppm. (SEPT 2022).

Currently I have my PO4 at 0.07 ish...and NO3 near 2 ppm. Routine weekly 10% water changes which includes siphoning the sandbed...needless to say - I upgraded most of my equipment and swapped out my T-5 light fixture for Metal Halide pendants. IMHO, BEST MOVE FOR ME.

 

[J1a]

Two more factors:

1. Availability of food in the water column, both dissolved and particulate food

2. Lack of predators, in particular those nippy fishes.

 

[i cant think]

I don't consider myself a newbie anymore but still young and learning! My current tank of just over a year (upgraded) astounds me with my coral growth including PE. I have a tenius that is positively fuzzy and some acros that browned when new and have come back with great PE and return of color and new growth. I love, at night, to take my blue flashlight and go spy on the corals and see who is out at night but not during day and make sure those out in daytime are still out at night. I have 3-4 corals I use to gauge things.

I think lights play a big part but agree that flow seems to be the big difference. I had 4 powerheads in the last tank and yet had horrible flow and corals struggling. This tank, 2 gyres and 2 mp40's and I attribute my so far success on having enough flow. Eventually I want to add 2 more mp40's.

I also find in this tank, no3 and po4 are much more stable even though it goes up and down. Right now I have another bout of algae--bryopsis again I think (3rd time) and zero no3 and po4 (last time I tested) Yet all looks fantastic (I believe the algae is consuming my no3 and po4). Will be adding reef flux in a day or 2.

One of the greatest joys is seeing happy corals!

recovering tyree Pinky the bear

Tenius

Yellow Tip Tort

Oregon Blue Tort finally showing growth and PE

I’m so glad I’m not the only one that struggled with the tort’s and getting them to show PE. My Oregon only recently showed PE however I haven’t seen growth out of it.

In my opinion, PE is good however I’ve found that the whole coral doesn’t need to show it. My Pearlberry doesn’t show PE where it grows up (Potentially due to it being a smooth skinned Acropora) however it does show PE where it’s branching out after it’s grown upwards.
But also, if you don’t have PE in the day then it’s not always a bad thing. The PE may just be in the night which is often normal on the wild due to predators in the day.

Here’s some of my Acros/SPS in my tank. The photos are under a filter so they do seem more orange. In person they’re much more vibrant.

Acropora valida (Tricolor)

Seriatopora caliendrum (Blue)

Montipora digitata (Orange & ‘Gold’)

Montipora spongoides (Green)

Acropora hyacinthus (Red Planet)

Acropora millepora (Red & Green)

Montipora spoingodes (Sunset)

 

[blaxsun]

I'm at the "enjoyment" stage of my tank as opposed to the "stressing out about coral growth" stage, so I honestly couldn't care less about PE. Is the coral dead? No - I'm ecstatic. Has one of my fish knocked it lose again? No - I'm equally ecstatic. Can I sit down and enjoy my tank and just watch the fish without having to do anything while I sip my hot cocoa? Yes - life is good.

 

[Reefahholic]

@jda prolly has some good opinions on this.

 

[i cant think]

I’m so glad I’m not the only one that struggled with the tort’s and getting them to show PE. My Oregon only recently showed PE however I haven’t seen growth out of it.

In my opinion, PE is good however I’ve found that the whole coral doesn’t need to show it. My Pearlberry doesn’t show PE where it grows up (Potentially due to it being a smooth skinned Acropora) however it does show PE where it’s branching out after it’s grown upwards.
But also, if you don’t have PE in the day then it’s not always a bad thing. The PE may just be in the night which is often normal on the wild due to predators in the day.

Here’s some of my Acros/SPS in my tank. The photos are under a filter so they do seem more orange. In person they’re much more vibrant.

Acropora valida (Tricolor)

Seriatopora caliendrum (Blue)

Montipora digitata (Orange & ‘Gold’)

Montipora spongoides (Green)

Acropora hyacinthus (Red Planet)

Acropora millepora (Red & Green)

Montipora spoingodes (Sunset)

I should probably also add that it depends on the coral - I prefer PE on all my corals however some don’t have it on the daily whilst others have it 24/7. My Leathers have it most of the time however they tend to close up every so often and don’t really open back up for a few days once shedding. My SPS have almost constant PE though whilst my LPS ‘shrink’ up during the night and then expand to be 5x the size in the morning.

So, some coral I do worry about when they don’t have PE however others (such as leathers) I don’t really worry about when they don’t show PE and don’t expand fully.

 

[ELChingonsReef]

I believe it’s very important.

If you’re not getting decent PE I think the first thing to consider is that some Acro’s just don’t have much PE to begin with. Others may not have much PE initially, but once they settle in, and become happy they develop some very nice PE that will shock you later.


There’s 4 factors I focus on in my tank that I feel are directly related to PE. If you can get these right (or close to right) then good PE will naturally follow. Here’s my .02 cents:

1. Chemistry- Dial in chemistry as much as possible. If some corals are lacking a few trace elements it can definitely affect PE.

2. Weak Flow- I’ve been a victim! Sometimes I feel like we think we have enough flow, but we really don’t. I have 6 Wave-Makers in a 105/G. 2x Nero 5’s, 2x Nero 3’s, 2x Jebao MLW 30’s. I feel like I could use 2 more. Acro’s can handle a ton of flow as long as it’s indirect and random. With all these Wave-Markers I have two corals that get perfect random flow that have a 50% higher growth rate on the sides that get blasted the most. Shockingly there’s still a lot of dead spots in the tank. I think strong random flow is very important for good PE.

3. Light- We know corals can adapt to many different PAR ranges. What they can’t adapt to is constant tinkering! Setup the lights, dial them in with a PAR meter and leave them alone. I can tell you that it’s very easy to play with LED channels and intensities.

4. Nutrients- This is tied in with chemistry, but can make or break a system. So for me NO3/PO4 need to be treated separately and require special attention (especially PO4). I’ve seen low or depleted PO4 completely affect PE. This is obviously different for every system and changes as the tank matures, but if you had a PO4 level of say .08 ppm, and then you notice 3 days later that PE is completely gone, it may be a good idea to check PO4 preferable with a Hanna ULR. If it tests at .01 ppm or zero then you have most likely found your problem. NO3 seems to be much less important, but if it sits a zero for too long it will lead to issues down the road. Don’t believe me, look at the pic below of my wife’s tank from about 3 years ago.

So are you saying that low phosphate causes cyano? I'm fighting cyano right now. I'm very frustrated. I baught chemiclean but I'm trying to do this without chemicals first then if i fail I'll use chemiclean. So my po4 stays mostly at 0.03 I have to dose 30 MLS of neophos constantly from brightwell to get it to stay at 0.05 .. if I stop dosing phosphate it drops back down. I have a red sea reefer 300L mixed reef it's a small 3ft tank nitrates stay around 10ppm . I do water changes every 7 days. I do 5 gallon changes weekly so the more water I change and cyano I cyphen the lower my phosphate gets. I have 3 echotech xr15 g5 lights running ab plus at 73% intensity. Maybe I should lower the whites? Do you have any advice for me on getting rid of cyano?

 

[Susan Edwards]

So are you saying that low phosphate causes cyano? I'm fighting cyano right now. I'm very frustrated. I baught chemiclean but I'm trying to do this without chemicals first then if i fail I'll use chemiclean. So my po4 stays mostly at 0.03 I have to dose 30 MLS of neophos constantly from brightwell to get it to stay at 0.05 .. if I stop dosing phosphate it drops back down. I have a red sea reefer 300L mixed reef it's a small 3ft tank nitrates stay around 10ppm . I do water changes every 7 days. I do 5 gallon changes weekly so the more water I change and cyano I cyphen the lower my phosphate gets. I have 3 echotech xr15 g5 lights running ab plus at 73% intensity. Maybe I should lower the whites? Do you have any advice for me on getting rid of cyano?

After trying to deal with it naturally I caved and used chemi clean. Gone in 24 hrs and hasn't been back since May. I'm battling the return of bryopsis so plan a 3rd round of reef flux. No3 at .3 and po4 at 0 but I know that is not so as the algae is consuming it. PE isn't being affected at all. Best PE ever right now. And no cyano. Dosing some neophos and have someone who wants some chaeto so will cut that in half. Not stopping my nopox as I can't say once the algae is gone what my numbers truly are. Might try to find the thread where some were dosing reef flux for preventative.

 

[Jeeperz]

I believe it’s very important.

If you’re not getting decent PE I think the first thing to consider is that some Acro’s just don’t have much PE to begin with. Others may not have much PE initially, but once they settle in, and become happy they develop some very nice PE that will shock you later.


There’s 4 factors I focus on in my tank that I feel are directly related to PE. If you can get these right (or close to right) then good PE will naturally follow. Here’s my .02 cents:

1. Chemistry- Dial in chemistry as much as possible. If some corals are lacking a few trace elements it can definitely affect PE.

2. Weak Flow- I’ve been a victim! Sometimes I feel like we think we have enough flow, but we really don’t. I have 6 Wave-Makers in a 105/G. 2x Nero 5’s, 2x Nero 3’s, 2x Jebao MLW 30’s. I feel like I could use 2 more. Acro’s can handle a ton of flow as long as it’s indirect and random. With all these Wave-Markers I have two corals that get perfect random flow that have a 50% higher growth rate on the sides that get blasted the most. Shockingly there’s still a lot of dead spots in the tank. I think strong random flow is very important for good PE.

3. Light- We know corals can adapt to many different PAR ranges. What they can’t adapt to is constant tinkering! Setup the lights, dial them in with a PAR meter and leave them alone. I can tell you that it’s very easy to play with LED channels and intensities.

4. Nutrients- This is tied in with chemistry, but can make or break a system. So for me NO3/PO4 need to be treated separately and require special attention (especially PO4). I’ve seen low or depleted PO4 completely affect PE. This is obviously different for every system and changes as the tank matures, but if you had a PO4 level of say .08 ppm, and then you notice 3 days later that PE is completely gone, it may be a good idea to check PO4 preferable with a Hanna ULR. If it tests at .01 ppm or zero then you have most likely found your problem. NO3 seems to be much less important, but if it sits a zero for too long it will lead to issues down the road. Don’t believe me, look at the pic below of my wife’s tank from about 3 years ago.

I'm dealing with this now, what was your fix? Just bringing nitrates up?

 

[Susan Edwards]

Or just wait. My yellow tort, started from a thumb size nub seldom had PE except some at night but not until it tripled in size. . It is now huge and has recently started showing PE during day. Perhaps they need a certain amt of growth?

I suspect there is no right or wrong answer here. It is coral dependent if your parameters and tank are where they should be. My no3 and po4 change. Sometimes bottom out, sometimes a bit higher than I prefer. The corals don't seem to care.