Encrusting vs branching/tabling

[Dkmoo]

Most of my corals seems to only want to encrust but I know they can grow "upwards".

Most of my acro encrust fast around the base but most branches don't have the "white tip" indicating growth

Montis spread out like a plague even for the species that supposed to grow "up" and has original upward nodes in the frag.

My acan/lepto/lepta/blastos/psammy frags all come with "thick" bone base plates. I can see head count double/triple all around the original frag but all are "flat" with no bone underneath.

One or two instances i can probably chalk that up to just that specific frag but this seem to happen system wide so im wondering if there are certain factors that promote the one form of growth over the other. Don't think its a calcification deficiency bx my params: 9alk, 470Cal, 1300 mag, 8.2 ph, 76F temp, 4 ppm no3, .01po4. PAR range from 400 for the acros and down to 50 for the lower lite LPS. I feed heavy and export heavy.

Seems its almost like the "reverse" of a burn tip syndrome conditions but I can't quite put my finger around it.

 

[SPR1968]

I ‘think’ sometimes it depends on the specific species and maybe water flow could affect it.

I have many SPS that grow sort of sideways towards the higher flow areas

 

[Suohhen]

Frags can be weird as well. Who knows what part of the colony they came from.

 

[Dkmoo]

Thanks for the responses.

My two current hypothesis is
1) calcification, while not deficient, is being outpaced by the "meat" growth due to my high nutrient thru-put.. compare that to my max ph of 8.2 and alk of 9, maybe i can slowly boost that even higher to the 8.3/10 range. I dont want to slow down meat growth by reducing nutrient/photoperiod so just want to think of ways to promote bone growth.

2) corals grow to the area thats "easiest" to grow to.. maybe I have a lot of empty rock real estate that once they start filling up and "sensing" its getting too close to another encruster that it'll then switch to growing "up". Time will tell.

At the end of the day the corals are healthy and growing so its not the end of the world..i just enjoy these "experiments" bc it keeps the hobby interesting and gives me more accurate insights/knowledge of my tank..

 

[T-J]

I'm going to resurrect this thread, as I was just about to post an Encrusting vs Growing thread.

My frags encrust. They encrust really nicely. Here's a pic of a couple of them showing how nice they cover their plugs in a few weeks. They even color up great. But, I too have the issue of actual "growth". Perhaps they need a certain level of encrustment (is that a word?) before they start growing up and out?

I've seen people say that gluing them sideways or nipping off the tips can help stimulate growth. Any truth to those (or other) techniques?

 

[Dkmoo]

I gave up trying to figure it out and just gonna chalk it up to "they grow whichever way is the easiest". I have to believe that million years of evolution would have made them already figured out a way to grow in a way that require the least amount if energy for the most amount of benefit. Which translated to tanks, probably is a function of specific flow patterns and par.

I had though it was a water chemistry issue where maybe I have too much nutrient and not enough alk/calc so meat was growing faster than bone.. Turned out that the "encrusting" still has calcium carbonate underneath so that kinda invalidated that theory.

 

[T-J]

My green slimer sat unchanged for about 6 months. Didn’t encrust. Didn’t grow at all. Then suddenly it took off. Nothing changed that I could tell. I think sometimes they need to settle in before growing.

 

[Suohhen]

It seems common for frags to do that on plugs but not so much on rock. I guess the smooth surface with no competition maybe has something to do with it.
Also there was a test done with various levels of phosphate that demonstrated that sps grows much more significantly in length at higher phosphate levels, up to .50 ppm iirc. But the gain in mass was the same across the board and every coral took months to settle in before really starting to reach out.

New study documents increased growth of staghorn Acropora in higher phosphate levels | Reef Builders | The Reef and Saltwater Aquarium Blog

Acropora corals are a mysterious creature with complex needs and one of those that we thought we’d nailed long ago was their “need” for minimal phosphate concentration in the water. A new study by…

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