View Full Version : How to promote Coralline Growth

03/20/2001, 09:33 AM
I just posted a new article on my website on Promoting Coralline growth.

Check it out (http://www.saltyzoo.com/CorallineGrowth.html) and give me some feedback.

03/20/2001, 12:32 PM
I have read that rock covered in coraline is a less effective bio-filter than rock without coraline. This certainly makes sense because the coraline basically seals the rock's pores reducing water flow into the surface.

Does anyone know of any testing that proves or disproves this theory? What do other reefers think of this idea?

03/20/2001, 12:38 PM
I have no doubt that this is true. Another reason to use LS as your primary bio-filtration.

03/20/2001, 01:29 PM
Great succinct article Greg.

I like that you included a list of coralline predators, you can add those little starfish (forget species but they are in hitchikers archive). I have watched several graze an area of coralline, leaving behind pale areas (slightly faster than watching grass grow).

I also have had a recent growth explosion of halimeda calcareous green macro algae. I am convinced that this rapidly depressed the calcium in solution and thus affected coralline growth.

I too am now using the Kent buffer and seachem calcium in an attempt to get things back to correct levels.

Some have suggested that coralline grows better with more actinic light. Any thoughts on this other than different species hypothesis?


03/20/2001, 01:45 PM
I read that brighter light stimulates the growth of the brighter and lighter shades of coraline and lower light levels/colors stimulate the darker coraline.

I suppose actinic light also brings out the contrast of the coraline making it easier to see. I notice that I get more pink under the MH but grow purple coraline in shadows.

03/20/2001, 01:47 PM
good artical gregt, One thing a lot of people dont know about calcium is that in order to keep or raise your calcium to the 400-450 level you have to maintain your stronium level. It is a complicated formala, but in lay terms you need to have your stronium at the proper level or your calcium will not raise or maintain. This is probibly why you had sucess when you did water change (you were adding stronium as well as other trace elements). If you dose with a stronium additive bring up the level you will have sucess with raising and maintaining your calcium.

It is true that different light levels will produce different types of calcerious algea. your purple corraline perfers lees light but it will still grow under intence light, just not as fast

From what I have read the rock Portion of Live rock does not play a big part in filtration, but the animals (micro algae, corraline algae, calcerious tube worms, fauna, ect) provide the filtration that we all desire.

03/20/2001, 01:54 PM

I forgot about those dreaded starfish! My choc. chip should have definitely made it into the article. Thanks for the reminder.


I've heard the "other trace element" concept, but it was magnesium, rather than strontium. Hmmm...

Raider Jeff
03/20/2001, 02:05 PM
You can add certain types, if not most, of urchins as coraline predators.

Greg - I would have to agree, I have heard and read the same about magnesium and I dose regularly as well. This is the first I've heard that about strontium. I have been told strotium does promote coraline algae growth though.

03/20/2001, 02:41 PM

here's a link to a thread on the little starfish. has a couple of links to more info. no mention as coralline eaters but I'm convinced they do.

03/20/2001, 04:34 PM
I have an Atlantic Blue Tang - and I have to tell you, this guy grazes on pink coralline algae like it was his last meal, then he killed all the caulerpa as well...
I have low light and coralline growing really well.

I have also seen coralline algae covered rocks around 60 fsw in 45 degree water up here. There's not a lot of light down there, however the sea urchins was found slightly deeper in 65 fsw and on sand bottom, not on coralline covered rock as one might expect - I was not doing scientific observations on that dive but I'll take a better look next time I got there - or if I see it in other places.


03/20/2001, 07:05 PM
hey guys,
i agree with you in that maintaining ALK and maybe pH are important factors. of course you need Ca, but you dont really need it at 400 or above for coraline. my reef has been set up in its current home for about a year now. coraline never really took off, or grew for that matter. as of late i have been more diligent in monitoring my water and i have been using superbuffer and turbo calcium. along with kalk. man o man the coraline has taken off like there's no tommorrow! i just wish more of it would grow on the rocks and not all over the freakin glass ;p

03/20/2001, 07:54 PM
I guarantee that strontium will cause the coralline algae to explode. Find a source for Strontium Chloride and mix up a 10% solution. For a 100 gallon tank add;

day 1 24.2 mL
day 2 24.2 mL
day 3 24.2 mL
day 4 24.2 mL
each week 3.9 mL

Within 1 week, you will see more coralline growth than ever before. I was getting really good growth when I was dosing the strontium with iodine and kalkwasser. I switched to the Restore product and the growth stopped. Last week I decided to add some more strontium and it took off again.

There may be several other ways to get the stuff to grow, but this is the easiest I have ever seen.

03/20/2001, 08:12 PM
My tank is FULL of coralline and I have never dosed Strontium. The only thing that I dose my tank is B-Ionic and sometime reef ca. My ca ranges from 410 to 460ppm and alka ranges from 9.2 - 10.6 dKh. I am not saying that dosing strontium and magnesium doesn't help as I am sure it would. In my case I have never added it. I use reef crystal and do a 10 water changes everyother week. Running 2 X 250 MH 12,000K and 2 X 96 PC 10,000K.

Even my clam shell is covered with it :)


My Site

03/20/2001, 08:21 PM
Indeed, toptank has the toptank when it comes to coralline algae. I have been trying to achieve something like that, with spurts of success. Unfortunately, my coralline algae doesn't look close to yours.

I have often wondered why I need to supplement strontium to get mine to grow. Obviously, some people don't need it. I just see a huge difference when I do.

I also use a 2-part calcium additive (Restore).

I just don't get it?

03/20/2001, 08:28 PM
Hi there !
I'm from Brazil and this is my second time here.
I asked Delbeck about this subject.
I asked him: Can the coraline alge compete for calcium and prejudice the coral's grown ?
He said that he thinks that is a good idea to keep a lot of corals because it's possible that dominate coraline can consume the calcium and it makes you add more calcium than you need to keep your corals healthy.

( I'm sorry about my English because it's not my language ok ?! )

[ ]s

03/20/2001, 09:31 PM
Coraline has its upside, but it can become a plague. I am sick of spending time using razor blades to scrape it off the front. I have noticed that the blue leg hermits and stars eat it off the back.

Good article BTW

03/23/2001, 07:52 PM
Yes it is hard to keep under control. I have to remove my PH about every 2weeks to clean them and the sides and front about every 3 days or so.


My Site: http://barryreef.homestead.com/index.html

03/23/2001, 08:22 PM
Hey O'man can you tell us your water parameters and also your type of calcium imput. THX

03/23/2001, 10:10 PM
Hey kmu:

Prams are: calcium... 380 to 460
alk........3.5 to 4.0 meq/l
nitrate, phosphate, ect are zero, but I only use hobbiest grade kits like fastest and hagen
specific gravity...22 to 24, depends on level of evaporation
I use seachem reef advantage and reef builder. These are great products, but do require monitoring of specific gravity. They will creep it up on you if you are not careful. I also use 2 part liquids like kent or bi-onic when I am in my lazy mode.

IME/IMO the seachem powders are best for raising levels. The 2 part liquids are best for maintaining existing levels.

03/24/2001, 06:35 AM
Greg; I agree with most. However, I have found the more intense the lights, the lighter the coralline colour.
Under Iwasaki,s its a pink/purple and under normal outputs its a darker, deeper purple. I even grew some maroon under normal bulbs. The darker also seems to love actinic colours, which of course is darker.

Magnesium & strontium, do indeed promote growth, of course with good levels of calcium.

One of the best additives for the growth of coralline is a two part ca/alk. supplement. I have had great success with both ESV & C-Balance.

Toptank, these two part supplements contain magnesium & strontium, along with other trace elements. Thats why they grow coralline well.

03/24/2001, 11:21 AM
hmmm... maybe i could do a little experiment. i have been monitoring my water religiously lately and maintaining Ca and Alk. at about 400 and 3.5meq/l and my coraline has taken off like wildfire! i will admit that i do not do water changes as often as i should, perhaps tommorow. but i dont see my tank getting any supplemental stront/mag. from any internal source. or any other trace elements for that matter. i'll look around and see if i have any supplements lying around and i'll try dosing them. see what happens. if i find some, what should i dose, half the recommended amount? BTW do supplements go bad? if i have some kickin around somewhere they are liable to be a few years old as i have stopped dosing stuff years ago, besides kalk that is.

just a thought

03/24/2001, 12:41 PM
No doubt the intense lights help. I have 2 tanks the 90 which I posted above but also have a 50 Gal with nothing but PCs and I took some of the LR out of my 90 gal that has the coralline 8 months ago and put it in the 50 gal and the coralline algae has spend very well under the PC. Ca and alka are the same in both tanks.


03/24/2001, 06:17 PM
Hey smokinreefer, whatcha dosing with for calcium and alk. P

On a side note, I forgot to mention that my turbos, love to eat coralline.

03/24/2001, 06:32 PM

Darker coralline species (purple) grow best under moderate light, while intense light like MH encourages lighter colored species to grow.
Good water flow (well oxygenated water) also helps to promote its growth.
B-Ionic is one of the best coralline algae enouragers. And there are a whole whack of "trace elements" in B-Ionic...not just calcium and buffer.

Here's an example from my old tank. I got sick and tired of trying to clean if from the glass, overflow box, etc. On my new tank, I'm working meticulously to keep it from growing anywhere but the rocks.


[Edited by Canadian on 03-25-2001 at 11:39 AM]

03/24/2001, 07:20 PM
hey doug,
i use turbocalcium and superbuffer. about 2 tsp a week of each and i drip kalk to compensate for evaporation, about one and a half gallons a day.

03/24/2001, 07:33 PM
I rarely see live rock come in with as much coraline as after it is in tanks for a few years, nor have I ever seen rocks that coraline covered in the wild (not that I've seen much of the world's reefs). Does coraline cover everything like this in the wild? What are we doing differently if it doesn't?

03/24/2001, 08:25 PM

Generally, most rock in the wild is not covered with that much coralline. However, I've noticed that the Fiji shaped with all the little round nodules tends to be almost 100% covered with coralline (straight from the reef). It's really hard to find pieces like that in the store, though.

Reasoning: Compared to the world's reefs, our tanks (such as the ones seen above)have a much higher ratio of corallines spores to water volume. Our tanks also have much less waste and nutrients in the water (for us to be successful, our water must be reasonably "clean"). In addition, reefs in the wild have more grazers, more variation is lighting due to depth differences, MUCH higher nutrient levels in the water, and more competitors of reef building elements, such as corals, algaes, etc. There's a whole bunch more factors I probably didn't mention.

Nice coralline growth, everyone. I will never achieve that level, because I definitely overfeed my tank (I have nice corals, though) and have excess PO4 in the water. Take it easy,


[Edited by bigben on 03-24-2001 at 10:31 PM]

03/25/2001, 07:39 AM
Just wondering what else besides kalk, you were using smokinreefer.

Most likely thats where your added elements are coming from.

Good post Andrew, completely agree.

Like others said though, be careful what you wish for. The coralline in my 170, consumes considerable amounts of calcium.

03/31/2001, 01:36 PM
<b>I've noticed that the Fiji shaped with all the little round nodules tends to be almost 100% covered with coralline (straight from the reef).</b>

I have some of this - anyone know what these are?

04/03/2001, 09:16 PM
Andrew aka Canadian

What type of lighting were you using on your old tank? Also what additives were you using? Do you have a web page?


04/03/2001, 09:31 PM

My old tank was a 20g with 4 x75W VHO lamps (1-50/50, 1-Actinic, 2-6500k). I pretty much used B-Ionic the first 8 months that tank was set up and then hooked up my Ca Reactor. All of the coralline in the picture was grown with B-Ionic. The Ca Reactor maintained what had grown.

Just click on the pic in my signature to see my old web site. I haven't really started the new site for my new tank yet.