Multiple questions on Ostreopsis Dinoflagellates

Snoopdog · Sep 2, 2020

I have a few questions on ostreopsis for the experts out there. I have pulled in multiple samples to a microscope and I am confused by a few things. When you see dinoflagellates under a microscope, what is actually making up the stringy slime in the aquarium? This is what is a mystery to me. Are the tiny organisms together making up the slime or are they producing something that looks like slime? I have read about these extensively from newer articles and articles dating back to the 70's and that is information that I have not been able to find. Looking under a microscope it looks more to be like they are surrounding what looks like algae and either creating it or eating it, they are doing "something to it". The visible portion looks like algae to me under a microscope. Also I notice mine even during a nightly blackout does not all enter the water column, a small portion does but absolutely not all of it. I have made some strides on lessening it over a 2 day period but it seemed to just came back heavy yesterday and I have no idea why. The only thing I did differently is lesson my manual removal for a day. I am not rushing to buy a uv light. Reason #1 I think the UV light just like total blackouts is just a band-aid over a problem. I think time and patience helps more than a UV light. Reason #2 - I do not mind doing this an experiment for others. I truly think you can go at this by adding biodiversity and being patient so I am going at this with adding live rock and nutrients exclusively.

The next question for those that may know the answer is why they thrive on low nutrients. Well I should ask for a friendly discussion because I have theories but do not completely understand our methods on eradication. If you look at how many people are having this problem, we have threads going as long as this forum has existed. If we did some analysis I would think the prevalence of dinoflagellates has increased over the years. So dinoflagellates would appear to get a foot hold in tanks that are not yet established and with people that start with dead rock, that is what I am seeing anyway. If you have no phosphates and no nitrates you are basically a ticking time bomb. If those do not exist then what are they getting for food in the tank? Are dinoflagellates starting to eat nitrates and phospates and decimating them to zero and when we see them the continually eat at them keeping them at zero? I have been feeding a well stocked tank for 7 days straight, often 5-7 times a day and my nitrates did not budge off of zero. I just have to think that live rock itself must help produce nitrates. I always had nitrates when I had 100% live rock in a tank, always. They seemed to average 10-30 points back when I had full live rock tanks and that was feeding once a day when I actually remembered. It may just be lack of patience at this point and I have not given it enough weeks/months of heavy feeding to see them raised, like I said it is just a thought. The theory is that when you can keep your phosphates up a tiny amount and keep your nitrates around 10 another algae comes in to compete with your problem dinoflagellates. That theory would seem to suggest the new algae, probably green hair algae is feeding off the excess nitrates. This is where I get confused though. Lets say green hair algae takes over, are you just giving yourself time for the microfauna to get a foothold? If your nitrates and phosphates dip back down later you just get another dinoflagellate outbreak correct? I guess my confusion is the consensus is to tell people not to run macro algae in the sump during an outbreak, but we are waiting on another algae like green hair algae to come in. I would think macro algae in a sump does the same thing for you, eat nutrients.

Sorry for all of the questions, I have just been puzzled by a problem that really was never a problem 'back in the day'

taricha · Sep 2, 2020

Snoopdog said:
This is what is a mystery to me. Are the tiny organisms together making up the slime or are they producing something that looks like slime?

They create mucus mats and generate microfibers. both help form long strings.
Linky
"Both in nature and in culture cells are embedded in a transparent matrix forming a continuous mucilaginous sheet (Figs. 2A–2F), which covers benthic surfaces (macroalgae, pebbles and rocks) and also the bottom of culture flasks. Often amorphous aggregates detach from the bottom, floating in the water column. Phase contrast microscopy shows that cells are connected to a complex and intricate network of tiny filaments (Fig. 2A). Cells are anchored to filaments from their ventral side, and are able of small rotatory movements around the point of attachment. In the field, also bacteria and diatoms are found to adhere to the filamentous network (Fig. 2A). Alcian Blue specific staining for sulphated and carboxylated polysaccharides [45] reveals the presence of abundant amorphous polysaccharidic material around cells (Fig. 2B): this stuff forms a transparent sheath embedding cells in larger aggregates connected by mucilaginous strands to other aggregates."

Snoopdog said:
So dinoflagellates would appear to get a foot hold in tanks that are not yet established and with people that start with dead rock, that is what I am seeing anyway. If you have no phosphates and no nitrates you are basically a ticking time bomb. If those do not exist then what are they getting for food in the tank?

It's not that they are getting zero N and P. It's more likely that they are better at exploiting organic forms that test poorly and we know they have an appetite for particulate forms. This means they do well on N and P sources that are local and that they can capture and exploit, while our tank tests low/zero on forms that are soluble and available to everything everywhere.

Short version of long answers. Or a start at least.

Snoopdog · Sep 2, 2020

Sorry, it has been a long day, it took me a while to get back to this post. So what about the macro algae theory? Why cannot we just take the nutrients out of the water using large copious amounts of macro algae? I thought that worked with things like green hair algae.