View Single Post
Old 08/16/2015, 11:04 PM   #1543
34cygni
Registered Member
 
Join Date: Mar 2013
Posts: 59
Quote:
Originally Posted by karimwassef
34... If your chain of events is correct, how do you link the UV results? In my case, it was a rapid decimation of dinos .

Maybe dead dinos become a good source for the competing bacteria and tips the scale.

If that's the case, then UV alone would be more effective that UV and skimming?
I haven't given a lot of thought to "the clean method", as it seems like how it works is straightforward enough, and my bias is towards bioremediation. But I fully understand that other hobbyists are into technological fixes, and I expect that if marine permaculture is possible, it'll be a thoughtful combination of these two different approaches that makes it work. So I'll take a stab at it.

It's certainly possible that lysing dinos and bacterioplankton and whatever else are releasing significant amounts of dissolved organic carbon into the system, as well as cellular detritus that gets skimmed off. This DOC would fuel the growth of heterotrophic bacteria and could perhaps result in the disruption of the dinos' little bacteria farms, but it could also fuel the little bacteria farms... In any case, Occam's Razor says that UVS is killing the free-swimming dinos, which are the adult dinos, meaning you're killing off most of the reproducing population -- fewer grown-ups means fewer babies.

But on the other hand, slow-flow UV sterilizes the heck out of the water column, which means that way fewer random bacteria and protists are floating around that could potentially get into the dinos' bacteria farms. Additionally, one of the papers I read mentioned that adding a solution of dissolved organic carbon extracted from red algae speeds up the growth of dinos in vitro -- like I said, DOC could also fuel the little bacteria farms... However, I don't know if this applies in axenic cultures or not, meaning I don't know if DOC boosts dino growth by boosting bacteria growth, or if dinos can directly absorb dissolved organic carbon from the water. There are hints that they can, and it makes sense that they can to at least some extent, given that they can utilize NO3 and PO4 directly from the water, but I haven't found proof.

Anyway, UV looks like a double-edged sword to me: it controls the dino population, but it may also help protect and nurture the survivors. I hope that's helpful.

And since you brought up UV, I did notice something in the thread that got me thinking...


Quote:
01/27/2015, 05:09 AM #680
Montireef
Completely agree, Dennis, specially on this:

"unlike the predators, the dinos can encyst and wait for the predators extinction, and then grow to plague proportions without any biological controls"

Almost one month later I am spotting some ostreopsis cells on the microscope. They were gone, but now they are back.


01/27/2015, 10:19 AM #681
PorkchopExpress
Really? Is your UV still online?


01/27/2015, 01:52 PM #682
Montireef
I never switch it off
The possibility that dinos could evolve UV resistance should not be dismissed out of hand. Everyone knows that dinos have an extensive bag of biochemical tricks to work with, and the reason for this is that they have honkin' huge genomes. The smallest dino genomes are larger than our own, and the largest known have an order of magnitude more DNA base pairs than we do. Dinos seem to be DNA hoarders, and given that C. taxifolia -- the seaweed that ate the Mediterranean -- came out of an aquarium, it's even crossed my mind that the invasive variant of O. ovata that's burning up the Med and the waters around Korea and Japan could have come out of a marine aquarium.

Molecular evidence for the aquarium origin of the green alga Caulerpa taxifolia introduced to the Mediterranean Sea
http://www.com.univ-mrs.fr/~boudoure..._1998_MEPS.pdf

UV resistant dinos would be bad. Imagine UV resistant O. ovata adapting to the intertidal zone.

Just thought that should be on the table, that's all.


Quote:
Originally Posted by DNA
34 Cygni, thanks for shedding light on several difficult issues.
LOL. My pleasure. I hope I can help, though do bear in mind that the foe in our crosshairs is one of the three main primary producers responsible for generating most of the biomass in modern marine ecosystems, the other two being diatoms and coccolithophores. That's why Quiet_Ivy has 2" of dino goo on her glass (I am in awe of that, BTW -- never seen it that bad). We are hunting big game, here, and failure is to be expected.

Quote:
Originally Posted by DNA
I've for long suspected bacteria to be a big player when it comes to dinos, but for reefkeepers they are hard to track for several reasons so they don't get discussed much here unless it's cyanobacteria.
You're absolutely headed in the right direction. Bacteria are players in all algae outbreaks, directly or indirectly, but most algae don't eat the bacteria...


Quote:
Originally Posted by DNA
If I disrupt both the cyano and dinos. Dinos will settle in their usual spots first and then the cyano will settle on top.
It's like the cyano is seeking out the dinos. It could also be the dinos are attracting the cyano for their benefit
The dinos are creating a phosphorous-rich microenvironment to recruit cyano. This kind of thing is very, very, very ancient behavior among single-celled organisms -- the Earth's ecology consisted of nothing but single-celled organisms for billions of years, and the highest evolutionary form they reached was a bacterial mat, a sort of bacterial biofilm on steroids in which a layer cake of many different microorganisms grow one on top of the other, passing nutrients from layer to another in a more or less cooperative manner. Bacterial mats are now rare outside of unusual environments like hot springs and hypersaline pools, but you can still see an echo of Earth's ancient ecosystem in a Winogradsky column, or in Shark Bay, Australia, or in the underlying microbiology of a deep sand bed.

Artificial Cyanobacterial Mats: Growth, Structure, and Vertical Zonation Patterns
http://bioold.science.ku.dk/mkuhl/pa...26Kuhl2000.pdf

Dinos also feed their "symbiotic" bacteria with simple organic carbon molecules that are like french fries for the bacteria -- not a lot of nutrition there, but a lot of calories. A lot of energy. All photoautotrophs seem to do this. When terrestrial plants are nutrient-limited, for example, they trade excess sugar generated by photosynthesis to fungi and bacteria in the soil in exchange for nutrients. Algaes do the same thing -- it's normal to find a few heterotrophic bacteria clinging onto the surface of individual phytoplankton cells, for example.


Quote:
Originally Posted by DNA
once this has taken place on the sand it can last for weeks. At least twice the end result has been a big reduction in dinos so one may think cyanobacteria to be a negative force on dinos.
On the last occasion on the other hand only few weeks ago the cyano left and didn't leave a dent in the dinos that have stayed at max densities since.
In my experience, the three-dimensional structures in which algaes present, whether it's a stringy mass of bubbly goo or a green shag carpet, are detritus traps to gather organic matter for their associated bacteria to break down, releasing nutrients that the algae needs. This, too, is an ancient strategy for gathering nutrients which was employed for billions of years by bacteria -- mature cyanobacterial mats, for example, are "phosphorous pumps" which trap so much detritus that even amidst a bunch of P-rich organisms like cyano and heterotrophic bacteria, there's excess PO4 generated by the bacterial decomposition of organic material. PO4 is practically insoluble in oxygenated seawater, so instead of being released into the water column, most of the excess PO4 diffuses out the bottom of the mat, into the anoxic water in the seafloor sediments.

Perhaps the cyano growing atop your ostis is sometimes able to collect enough detritus to contaminate the dinos' bacteria farm or attract other, hungrier protists and microfauna that quietly ate their way through the dino bloom.

Other possibilities that occur to me are that the cyano grew so thick and lush that it prevented the dinos from photosynthesizing effectively, or that the cyano produced toxins of its own and fought back. However, it seems unlikely that cyano would be able to shade out the dinos, as dinos (like all freshwater and marine algaes that I'm aware of) can adjust their photosynthesis machinery to work with less light. It also seems unlikely that dinos would recruit a species of cyano that could poison them -- behavior like that should be edited out of the species by evolution.

Thus, it appears that letting the cyano grow may be another backdoor route to "the dirty method", like Montireef's probiotic tea.


Quote:
Originally Posted by DNA
It seems like it's difficult for reefers and scientists to get the same results repeatedly or the dynamics and adaptations of the dinos are playing trics on us.
Most scientist admit they don't know enough and further studies to be needed.
That paper proposing that mixotrophic dinos obtain P from bacteria and N from cyano dates from 2010, and it's apparently the first time the idea was put in print -- or at least the first time the lead author of the paper was aware of it being put in print, as he used the phrase "I propose a possible mechanism". That was just 5 years ago. Think about it: we're about as close to the cutting edge of science as reefers are ever likely to get. If we finally have a viable mental model of what's going on, we finally have a chance -- maybe not a big one, but a chance just the same -- to think our way through this thing.


Quote:
Originally Posted by DNA
A natural dino bloom has been described to have a rubber band effect with the predators in tow.
The predators will always catch up and the bloom will reside.
Yes, that's broadly true of trophic relationships across all ecosystems at every level. Fluctuations in the population of bunnies will "rubber band" the populations of predators that feed on rabbits, for example, and the population of bunnies fluctuates in part because they're being "rubber banded" by the changing fortunes of the plants they eat (for example, less rain = less plants = less bunnies). An ecosystem can be viewed as a rat's nest of interlocking feedback loops with no true equilibrium point.


Quote:
Originally Posted by DNA
In my closed ecosystem there has been a constant mild bloom for years and predators have never got the upper hand.
Unfortunately this law of nature does not apply in my reef tank, but still my bloom has not exceeded mild for a long time.
It's the toxins that trouble me. Of course, GAC saves the day, and this hobby requires so many consumables already that what's one more? But I don't like to see hobbyists stuck on yet another treadmill, especially when an equipment failure could potentially cause real heartbreak, or even pose a health risk.


Quote:
Originally Posted by Pants
I didn't see much discussion here about the toxins produced by these guys and wanted to make sure everyone is taking proper precautions.

Ostreopsis sp. makes palytoxin. This is a toxin all reefers should be familiar with as palythoas and zoanthids produce this toxin and there are stories every year of hobbyists nearly killing themselves by mishandling these corals. Amphidinium isn't really thought of as highly toxic, but I've talked to too many reefers with Amphidinium blooms who have experienced personal health effects when killing these that I think we should treat Amphidinium with respect as well.

The dinos won't release the toxin until they die, so before starting any eradication procedures you should make sure the area around the tank is well ventilated, and have carbon ready to run. It would be a good idea to keep everyone (including other pets) away from the tank and wear gloves and a mask if you are getting a lot of dino die off.
Ecology and oceanography of harmful marine microalgae
https://www.terrapub.co.jp/e-library...ishida_023.pdf


Quote:
Originally Posted by DNA
I kept my skimmer running after pouring the skimmate in.
If Montireef confirms that his skimmer was off, I encourage you to try again, this time following the Montireef Protocol.

I understand your reluctance. Saltwater hobbyists are often brimming with energy, invention, and inquisitiveness, but at the same time the more deeply invested we are in our systems -- not just in terms of time and energy and money, but emotionally invested, as well -- the more conservative we become. We don't want to put at risk all that we have accomplished, to say nothing of livestock that we're proud of or sentimental about.

But I submit that if you're ever going to try it, now's the time.

Reason one: Your new LR and sand is probably still cycling. Maybe this is important, maybe it isn't. Let's worry about that later.

Reason two: You've made your corals, and in particular their zooxanthellic symbionts (...which are dinos, do bear in mind) very happy with all that nitrogen you've released into the system. Corals keep their symbionts nitrogen-limited to force them to pump out sugar, and as much as half of this sugar goes towards making mucous -- which sounds a little disgusting until you consider that mucous is the front line of coral's immune system. They secrete mucous to lift bacteria off their surface, and then release the mucous into the water, and the bacteria drift harmlessly away. Right now, your corals' symbionts are PUMPED! They've finally gotten the nitrogen they crave -- that's why they colored up. The corals may even have let them have enough nitrogen to multiply. With all those healthy, happy symbionts, your corals are in about as good a position to protect themselves from an onslaught of bacteria as they ever will be.

Reason three: If Montireef dosed with his skimmer off, then you've proven that the Montireef Protocol doesn't work with the skimmer on. That's useful information. The obvious next experiment to try is to test whether or not the skimmer really is the variable by dosing again with it off, and only you can do that experiment because it should be run in the same system under similar conditions.

Reason four: You've held this thread together, kept it on topic, and driven the discussion forward for TWO YEARS. You were the one who called everyone's attention to what Montireef did:

Quote:
Originally Posted by DNA
Did you miss the possible cure for Ostreopsis dinoflagellates?

Montireefs claims need to be repeated by several third parties.
He got rid of them with two kilos of fresh live rock and 2 liters of skimmate.
With donated tank water two more reefers got rid of them as well.
He's got videos to back up what seems to be microbes attacking the dinos.
He's identified his dinos with a microscope.

Drop your gut feeling and let's prove if this really works.
I ask you to accept your own advice.

Reason five: Curiosity. Just simple curiosity.

And, of course, if Montireef pops up and says, "I don't know what you're talking about, 34cygni -- my skimmer was on the whole time" then I wasted my time composing all that and will feel duly embarrassed. But that black snail poop... I just have a feeling his skimmer was off, and I'm willing to go out on a limb occasionally looking for the leverage to push the hobby forward another inch or two.


34cygni is offline   Reply With Quote