How fast do coral grow?

[MnFish1]

So - everyone here with an SPS related tank is concerned about growth. Without googling. What is the maximum growth to expect from SPS within a year?

 

[Charlie’s Frags]

These before and afters are almost exactly 1 year apart

 

[KrisReef]

I would expect the average maximum growth rate in the wild to be higher than what we see in our tanks.
Our tanks would likely have more instances of zero growth than found in the wild?

 

[MnFish1]

I would expect the average maximum growth rate in the wild to be higher than what we see in our tanks.
Our tanks would likely have more instances of zero growth than found in the wild?

Why?

 

[MnFish1]

Why?

Sorry - I meant 'why' - assuming we're doing everything correctly - on average lots of people probably aren't.

 

[Charlie’s Frags]

Why?

Ideal and stable water chemistry, natural wave action, intense sun light and lunar cycle, and an infinite supply of zooplankton. Assuming we’re discussing a healthy reef. All of these are impossible to reproduce in a box of water.

 

[Bob Weigant]

I’ve had corals either grow from the get go or not do anything for an extended amount of time then one day they just take off. They tend to always look good but I’ve never understood why some grow faster than others

 

[SeaDweller]

Depends: I have some dormant stuff that haven't grown in almost a year and some that have grown so much (2+") in under a year.

 

[KrisReef]

Why?

What @Chaswood79 said pretty much covered it. Again, talking AVERAGE wildreef vs. Average captive reef.

Also, I've had high variability between coral growth rates in my home system. Montipora caps, digitata & setosa that have exploded, and other monties that did not exhibit the same growth rates?

Other SPS frags, some melt (negative growth rate) while others grow slowly, and still others explode. Why? Because that is what they do.

Do our systems provide for faster growth than the wild? Probably sometimes.

 

[SeaDweller]

I swear on some pieces I can see them "inching" closer and closer each day, I know they're growing fractions of mm each day, and within a week, some touch. I don't know the process of adding skeleton to existing skeleton and the flesh, etc, but its pretty fascinating if you think of it. This is such a slow process, but I'm sure most of us that are in tune with our tanks and know them so well can see the changes literally each day.

 

[DesertReefT4r]

Asking how fast coral grows is like asking how long is a piece of string. There are so many variables that effect coral growth. A short answer is under ideal conditions sps corals can grow quickly under poor conditions they can grow very slowly or not at all.

 

[ScottR]

So - everyone here with an SPS related tank is concerned about growth. Without googling. What is the maximum growth to expect from SPS within a year?

@MnFish1 - you’re trying to open a can of worms here aren’t you? ;Hilarious If anyone posts the same two answers in this post, I’ll donate a kidney to charity. And maybe a Starbucks gift card.

 

[tnyr5]

In a year? 6 to 9 inches on the fast growers.

 

[nitrodude]

Like everyone's said this is pretty impossible to answer.
Some stuff grows rapidly while others dont.
Plus growth is also linear, a 1/2" frag vs a 1ft colony with dozens of branches-the large colony will grow faster then the tiny frag.

I've had small frags stay exactly the same for almost a year with no visible growth, and I've had corals like green digi that went from a 1/2" frag to a massive colony in less then a year.

 

[TARHEEL78]

The correct answer to this question is "Not fast enough".

 

[MnFish1]

Like everyone's said this is pretty impossible to answer.
Some stuff grows rapidly while others dont.
Plus growth is also linear, a 1/2" frag vs a 1ft colony with dozens of branches-the large colony will grow faster then the tiny frag.

I've had small frags stay exactly the same for almost a year with no visible growth, and I've had corals like green digi that went from a 1/2" frag to a massive colony in less then a year.

Its not impossible to answer - there is data 'out there' that suggests the maximum a coral should grow in a year - just curious if we (in our tanks are meeting.beating that estimate)

 

[MnFish1]

Asking how fast coral grows is like asking how long is a piece of string. There are so many variables that effect coral growth. A short answer is under ideal conditions sps corals can grow quickly under poor conditions they can grow very slowly or not at all.

No - I'm asking how fast 'your' coral is growing. lol. If you keep corals under poor conditions that your problem. I'm not asking you to decide 'the average' - BUT - what your tank is doing

 

[MnFish1]

Ideal and stable water chemistry, natural wave action, intense sun light and lunar cycle, and an infinite supply of zooplankton. Assuming we’re discussing a healthy reef. All of these are impossible to reproduce in a box of water.

If thats the case - then those of us who 'pretend' to be preserving reefs should get another job? actually - I'm sure many people achieve the growth rates possible;0

 

[MnFish1]

Depends: I have some dormant stuff that haven't grown in almost a year and some that have grown so much (2+") in under a year.

Why do you think that is?

 

[erk]

1 million inches.

Length isn't the best way to measure coral growth, SPS or not. Coral mass is more accurate. Depending on environment, corals may bulk up and increase mass while showing very little growth that we notice. This is because no two aquariums are the same.

Flow for instance is completely subjective. Only Dana Riddle has a flow sensor to accurately measure water movement in a tank. So one person's high flow is another person's stagnant cess pool. Then there is light. Let's not get into light. Then stability of parameters, levels of those parameters, etc. There is also the situation where optimal growth conditions for corals is very large. I mean, take into consideration the discovery of the coral reef at the exit of the Amazon river. A highly turbid, relatively low light(compared to Caribbean and Pacific reefs) and nutrient rich area. Not really considered to be the best place for coral. Yet there is a massive reef chain there. This is in total contrast to the Pacific reefs.

If the very equipment we use is typically judged subjectively, you can darn well bet that hobbyists are going to judge coral growth subjectively as well. I doubt anyone but research groups are pulling corals out of tanks to weigh and measure them to document coral growth.

So, do I think there are those able to grow corals at similar rates to what we observe in the wild, sure. But which wild environment? Reef slope? Lagoon? Turbid reefs? Deep water? Low tide exposed reefs? The shallow reefs actually experience stunting due to the excessive PAR. Learned that from a MACNA talk that Dana did in 2016. I think it was 2016. The one where he observed the Porites in the shallow pools in Hawaii. Actually, since that talk I now use a black light to check the fluorescence of my coral to see where the coral is photosynthetically active. When healthy, the SPS fluoresce most brilliantly at the polyps and less so on the corallite.