Is Green Coraline a real thing?

[boscoT]

I am using caribsea life rock for the first time as I always used Fiji rock in my tanks over 12 years ago. With that said, implementing Coraline algae has never been something that I have had to do.  

 

Tank is in its third month.  Diatoms are almost clear, ammonia 0, nitrate 2ppm, phosphate 2ppb, alk 8dkh

 

Water is crystal clear, and my lighting schedule is a reduced Eddie Putra AI prime 16hd reduced to 25% strength

 

I introduced coraline algae over a month ago from my LFS.  They gave me a large piece that I crunched up and spread throughout the tank.  The tank looks normal and purple under the blue lights, however; when I go to regular white light I have noticed a lime green coating on my rock.  It isn't fuzzy or hairy, it doesn't feel slippery like normal algae. A toothbrush scrub doesn't want to remove it either.  

 

A quick google search, I found several posts suggesting that what I am seeing is possibly green Coraline.  Something that is common before purple Coraline develops.  

 

My water is clear, no brown at all as I am doing 50% water changes weekly while the tank is breaking in.  

 

Can anyone comment if this is problem algae or more of this green Coraline (a good thing from what I have been reading)

 

I am using home made RODI water with a 4 stage unit and reading of 0 TDS.  I have also confirmed with my local municipality that my silicon level is 0.27 to 0.85 mg/L

 

[william_payne1]

That is what the rocks in my 50gal looked like just before the purple coralline started to grow on the green areas, but it is a possibility that it is green coralline, mine wasn't such a bright lime color like that it was more muted.  

[boscoT]

18 minutes ago, william_payne1 said:

That is what the rocks in my 50gal looked like just before the purple coralline started to grow on the green areas, but it is a possibility that it is green coralline, mine wasn't such a bright lime color like that it was more muted.  

What time frame did it show up in your tank?

[william_payne1]

4 hours ago, boscoT said:

What time frame did it show up in your tank?

About a month after seeding it I noticed dark green blotches (almost like diatoms but very green) and I was worried it might be something bad, but it didn't come off the rocks easily and it was smoother than other green algae blooms, but it slowly started getting covered by the purple plating coralline which took longer to happen but I added Instant Ocean Reef Accelerator for about three weeks and it took off. I think just having your cal. around 400-450 will do the same but the IO stuff adds some other trace elements as well. I now use SEA-LAB No28 after having good results with it in my SPS Pico tank, but I have also used C-Balance with good results in my larger tanks. 

[Rhetoric]

I started with dry rock almost a year ago, all of my rock has a green coloration to it.  Can't really see it with the lights on.   I'm not sure if it's coralline or not.  I do have purple growing slowly.  I don't think it's hurting anything and feels like the natural process to me.

 

If it doesn't get fuzzy, long and stringy, or bubbly then I'm not worried.

 

 

[boscoT]

23 minutes ago, Rhetoric said:

If it doesn't get fuzzy, long and stringy, or bubbly then I'm not worried.

This sounds like my thought process.  
 

Maybe it’s just a thing with the caribsea live rock.  I’m not going to worry about it anymore as all of the parameters are good.   
 

thanks for the comment 

[Murphs_Reef]

Coraline comes in various colours, from deep purple to dark reds, greens and almost black in colour. 

[mcarroll]

On 11/11/2023 at 7:50 PM, boscoT said:

nitrate 2ppm, phosphate 2ppb

IMO you aren't going to grow the algae you want to see with nutrient levels so low.

 

FYI, 2ppb = 0.006 ppm PO4.   Effectively zero.

 

On 11/11/2023 at 7:50 PM, boscoT said:

my lighting schedule is a reduced Eddie Putra AI prime 16hd reduced to 25% strength

Hm.   Eddie Putra + Prime 16hd - 25% = ...??

 

Either you'll have to define those terms for me... 🤪 ...or download a free smartphone lux meter app (eg Galactica Luxmeter) and tell me how much light the tank is getting (in lux) at whatever the peak of the day is.  🙂 👍

 

On 11/11/2023 at 7:50 PM, boscoT said:

I found several posts suggesting that what I am seeing is possibly green Coraline.

I more suspect that it's green slime algae, aka green cyano.   Makes more sense given your numbers and situation.

 

On 11/11/2023 at 7:50 PM, boscoT said:

I am doing 50% water changes weekly while the tank is breaking in

Sound like you're overdoing it by about a mile. 😉   Take it easy on the water changes and see if your nutrient levels normalize.  

 

You want phosphate levels to be NO LESS than 0.03 ppm (about 10 ppb)...and levels higher than that are OK.  

 

For the time being, unless PO4 is at least 0.10 ppm (about 33 ppb) I would not do a water change.  Hopefully NO3 will also increase a little, or not drop to 0 ppm at the very least.

 

The green cyano may give up on its own once conditions become more favorable for green hair and coralline algae.

 

Nutrients are OK to have.  🙂 👍

 

BTW.....I really like your rock structure!   Will be nice to populate once things get rolling!  🙂 

[boscoT]

52 minutes ago, mcarroll said:

MO you aren't going to grow the algae you want to see with nutrient levels so low.

 

FYI, 2ppb = 0.006 ppm PO4.   Effectively zero.

I just tested the water tonight after 10 days

 

                    NH3 0           NO3 ppm       PO4 ppb       Alk 7.7dkh

 

Levels have creeped up over the past 10 days.  Perhaps more flow stirring things up, or 3 days of lights out has caused some die off?  Numbers appear more where you have recommended.  Everything that I am reading suggests keeps NO3 and N\PO4 as low as possible.  I guess this is wrong?

 

As for lighting, I am not sure about the readings.  The 25% basically, I took the program and reduced it by 75% efficiency.  For now I am trying to not use too much lighting but enough to enjoy it throughout the day.  Ill have to get back to you at some point

 

52 minutes ago, mcarroll said:

I more suspect that it's green slime algae, aka green cyano.   Makes more sense given your numbers and situation.

I disagree with your suspicion.  I worked in an aquarium store for several years and have been involved with aquariums for many years.  This is not slime algae in anyway.  It feels like absolutely nothing is on the rock.  It doesn't rub off with tooth brush either.  That's what made me ask about this.  I know you will ask me to check a microscope to confirm, however; I am not ready to dive into that either at this time.  

 

I did do a water change this week, but I will go a week to start and see where my numbers end up if you think that will help.  Are you suggesting that if this is green cyano, I am going to have a green algae spike once my NO3 and PO4 start to rise?  I didn't understand that part of your comment.  

 

As for the rock structure, I am excited to get some corals going, I am just not wanting to add any until I feel more confident about the water chemistry.  I need to wrap my mind around increasing NO3 and PO4 an not keeping them as close to zero as possible.  I will try anything!!

 

[boscoT]

@mcarroll I just googled algae and if I were to guess... I am leaning towards green film algae perhaps.  Definitely not cyano from all of the things that I have viewed.  

[MrP]

4 hours ago, boscoT said:

I just googled algae and if I were to guess... I am leaning towards green film algae perhaps.  Definitely not cyano from all of the things that I have viewed.  

It is definitely a green film algae. I've heard lots of people claim that this is the precursor of coralline which I don't think is true. The rock is just in the process of becoming live. Green coralline does exist but it isn't common to see and it is one of the slower growing corallines. It definitely wouldn't be able to cover that much area in such a short amount of time.

[mcarroll]

16 hours ago, boscoT said:

Everything that I am reading suggests keeps NO3 and N\PO4 as low as possible.  I guess this is wrong?

If you could tell me what you read exactly, it would help.  (Links if possible.)  

 

If you literally read that, as in read it in a book, then "as low as possible" was just an ideal that was expressed, not a goal that anyone ever reached.  For example, in "Corals..." by Eric Borneman it says phosphate levels should be "undetectable" when he talks about control.  He doesn't even mention a number, let alone "0.00 ppm".  In context, "undetectable" when you're using drip tests means "can't read the chart any lower"...

 

If you've used one of these kits (they're still common...and useful!!) then you know, once levels get under 0.10 ppm it can be hard-to-impossible to discern a precise reading.

 

In most cases, this dynamic prevented anyone's tank from even APPROACHING 0.00 ppm....always leaving plenty of phosphates for coral happiness.

 

 

In addition, it was (and still is) a common stereotype that reefs love low nutrient water.  Knowing what we know today, that is a drastically misleading oversimplification.  Reefs need nutrients like any other kind of critter.

 

Unfortunately, several (mostly) bad things converged around this leading up to the 2010's....

• hobbyist fear of algae (lack of understanding)
• reef stereotypes (ie "pristine reef" mentality)
• whole-tank carbon dosing
• phosphate-adsorbing media
• lanthanum chloride dosing
• test kits accurate to near-zero ppm
• live rock became unavailable
• ...just off the top of my head

Once these things were all in-play at once, the "nutrients as low as possible" strategy changed from a simplistic ideal to being an outright problem.

 

16 hours ago, boscoT said:

@mcarroll I just googled algae and if I were to guess... I am leaning towards green film algae perhaps.  Definitely not cyano from all of the things that I have viewed.  

I think "green film" and "green slime" and cyanobacteria (aka cyano) are all the same thing....all relating to nutrients being too low to support "better" algae.  👍

 

Green is just the least common cyano to see in saltwater, BTW.  Most folks never get more than a hint of it before more dominant critters (often other algae) take over their rock.   "Red slime" is the most common cyano.   I think green is a little more common in freshwater tanks....but it tends to look black.

 

16 hours ago, boscoT said:

It doesn't rub off with tooth brush either.  That's what made me ask about this.

There are other possibilities, but they are less likely IMO – such as green boring algae.  Boring algae are fairly common, though not often seen – they subsist off of nutrients (especially phosphates) within the rock.  Ordinarily they grow inside of coral skeletons, often under the flesh completely out of sight.  Check out the article "The in situ light microenvironment of corals" for more info on this.

 

I think more to the point is that your algae (unfortunately) doesn't seem like coralline algae, which is what you really want.  You should be able to flake off a little if it's coralline.

 

A microscope shot would be nice, but if you can't remove it from the rocks then the point is moot.  👍

 

16 hours ago, boscoT said:

Are you suggesting that if this is green cyano, I am going to have a green algae spike once my NO3 and PO4 start to rise?  I didn't understand that part of your comment.  

You will be hoping for that, in fact.  As long as nutrient levels remain relatively low (just not near-zero), the "spike" should be small and pretty manageable.

 

Green algae (ie hair) and coralline both like about the same conditions, nutrient-wise and light-wise.  (Hair algae probably tolerates higher light levels tho.)

 

CUC is what holds back the green algae from dominating....and allows the coralline algae (and corals) to take over instead.   So be johnny-on-the-spot with more snails once you see some algae sprouting.   (In fact, hopefully you have a little CUC in there already.)

 

16 hours ago, boscoT said:

As for the rock structure, I am excited to get some corals going, I am just not wanting to add any until I feel more confident about the water chemistry.  I need to wrap my mind around increasing NO3 and PO4 an not keeping them as close to zero as possible.  I will try anything!!

The problem with the "near zero" angle is that nutrient cycles in the wild are VERY different from the nutrient load in our tanks.  

 

In the wild nutrient levels around most reefs ARE low....but not as a precondition for the reef.  Again, that's more or less a stereotype.  Reefs come in MANY flavors – not just one.  If we were to generalize, reefs actually need LOTS of nutrients. If there's no nutrient source, there's no reef. 

 

Getting back to how wild is different from our tanks...there are two crucial nutrient sources in the wild that our home reef tanks generally lack.  One is detritus and the other is suspended aragonite sediments.  Both are usually significant food sources for most wild reefs and supply corals with much-needed phosphate among other things.  This allows corals on wild reefs to subsist apparently without good access to dissolved nutrients...PO4 in particular.

 

Check out the range of scientific journal articles I've saved relating to coral nutrition for more background on this.  There has been a TON of research in the last 10-15 years.

 

The fact is (and it shouldn't be too surprising) that corals need nutrients just like any other plant or animal – and even more-so since they are a hybrid (if you will) plant-and-animal.  Not only do they require all the same things that any animal on the reef requires....but they also must meet the needs of their photosynthetic dinoflagellate endosymbionts.

 

In general, as long as aquarium corals aren't starved of PO4 they will be pretty happy even if nitrate levels are quite low, even near-zero.  (There are many forms of nitrogen that corals usually have access to other than nitrate.....so unlike with PO4, even when nitrates are 0.00 there are still sources of N available.   Amino acids, uric acid, ammonia, etc.)

[boscoT]

Just to add to this post.  I have noticed pink spots starting to pop up all over my green spots.  I also found some coraline algae growth on my keep 3 today.  I seeded the tank with some coraline that Fragbox gave me two months ago.  I crushed it up and spread it throughout the tank.  Maybe not green coraline but it has never changed colour since it showed up and it has never developed any problem algae since.  Now it’s getting covered in coraline spores from what I can see. Either way things are clearly moving in the right direction!!!!