Symbiodinium. Got any treatment ideas?

[ScottB]

While it looks kinda similar to ostreopsis in the tank, it is very different under the scope. They are VERY small and completely motionless.

They are easily basted or siphoned away but return the next day. They don't stick to coral flesh, but do stick to everything else. I FEEL like they are beating on my coralline but may be mixing cause with effect.

My nutrients are generous and stable around .1/10 for PO4 and NO3. Salinity, temps and ICP numbers are all nominal minus a trace or two.

They might have first appeared a few months ago when nitrates were a little higher and I was gradually drawing them down with WC and carbon dosing (vinegar) which I then weaned off. Now these things are accelerating a bit. I have to baste every 2 days or I cannot look at my tanks. Both systems now have them.

I feed heavy with frozen and nori. My (120G) display has just a skimmer, socks and WC for export. My (300G) frag system has the same plus large refugium. Both systems have significant flow for SPS. These do grow only in the low flow areas of the tanks.

So a few questions:
1) Agree my ID?
2) Why are they so dang happy in my systems?
3) How can I manage these things down?

 

[ScottB]

Forgot to tag @taricha

 

[taricha]

Signs of chrysophytes:

blobby gelatinous mucus
sometimes mucus so strong it holds shape out of water
light brown/tan/gold
under microscope, embedded in thick mucus
cells spaced out in the embedded mucus
cells are super tiny
cells nearly spherical
cells totally motionless

looks like you check 7 of the 8 boxes, (maybe not number 2)
pretty certain it's Chrysophytes

posted this in another thread, but it applies here as well.
Two recent outbreaks I've seen of these guys

https://www.reef2reef.com/threads/help-identify-brown-plaque.803590/
https://www.reef2reef.com/threads/dino-id.796294/

Go to threads for what people are doing against these.
https://www.reef2reef.com/threads/chrysophytes-help-me-cure-it.263759/
https://www.reef2reef.com/threads/c...fy-treat-and-remove-it-from-your-tank.299585/

 

[ScottB]

posted this in another thread, but it applies here as well.
Two recent outbreaks I've seen of these guys

https://www.reef2reef.com/threads/help-identify-brown-plaque.803590/
https://www.reef2reef.com/threads/dino-id.796294/

Go to threads for what people are doing against these.
https://www.reef2reef.com/threads/chrysophytes-help-me-cure-it.263759/
https://www.reef2reef.com/threads/c...fy-treat-and-remove-it-from-your-tank.299585/

Thanks taricha. I got through all the posts. Kinda reminds me of large cell amphids where treatment protocol is all over the map.

So a few reported success with Fluconazole, but to me that is a Hail Mary action. I have too much invested in named acropora and don't want to be one of the admittedly small number that wipe everything out with fluc.

Vibrant or Dr Tims was another vein, but kinda weak. Come to think of it, I started dosing MB7 when I first started seeing this in my frag system and it has gotten worse, not better.

Manual removal and blackout seems common. I've done the removal work many times, but have not blacked out yet.

It does not really seem to be bothering my corals much if at all. (I have aefw for that )

What would you do next?

 

[taricha]

Good question. Just because they look like dinos, I would not make any assumptions. Somebody sent me a sample of these once, and they cultured up nicely on F2 phyto growth media, which means they are much easier to grow in high nutrient conditions than dinos are.
Although I don't know of any reports of UV working against them, the stringy nature might indicate that there is some dispersal into the water and reassembly happening. Long story short, I would put nutrients at whatever levels the coral are happy with, run UV, run GAC just in case. I'd hang filter floss in the flow in front of a powerhead, and check it for any accumulation of brown or goo, that would tell me it's going into the water. I'd manually remove as you are already doing.
Next steps, if after a week or so I don't like where things are. I might add Si just because I'd rather have diatoms fill the niche, and possibly short blackout 24 or 36hr to see if low light stress might push them to break up and take to the water and get hit by uv.

 

[ScottB]

Good question. Just because they look like dinos, I would not make any assumptions. Somebody sent me a sample of these once, and they cultured up nicely on F2 phyto growth media, which means they are much easier to grow in high nutrient conditions than dinos are.
Although I don't know of any reports of UV working against them, the stringy nature might indicate that there is some dispersal into the water and reassembly happening. Long story short, I would put nutrients at whatever levels the coral are happy with, run UV, run GAC just in case. I'd hang filter floss in the flow in front of a powerhead, and check it for any accumulation of brown or goo, that would tell me it's going into the water. I'd manually remove as you are already doing.
Next steps, if after a week or so I don't like where things are. I might add Si just because I'd rather have diatoms fill the niche, and possibly short blackout 24 or 36hr to see if low light stress might push them to break up and take to the water and get hit by uv.

Many thanks. That is a very familiar protocol that I should be able to execute with ease. Would be good if that stuff was happy to collect on some floss. Will report back in a couple days

 

[taricha]

Would be good if that stuff was happy to collect on some floss.

Actually, If it were me, I would add the filter floss a couple of days before adding UV. Because frankly I would just be really curious and checking the filter floss might tell us a lot about the behavior that we don't know.

 

[ScottB]

Actually, If it were me, I would add the filter floss a couple of days before adding UV. Because frankly I would just be really curious and checking the filter floss might tell us a lot about the behavior that we don't know.

Well, as I have the issue in both systems, I will apply UV to one (frag system) and filter floss to the other. Manual removal by siphon will happen on both.

 

[taricha]

@ScottB this BRS video I just ran across makes a convincing demo that UV will not be effective (see around 13 min mark).

chrysophytes took over multiple tanks with UV in place.

 

[ScottB]

@ScottB this BRS video I just ran across makes a convincing demo that UV will not be effective (see around 13 min mark).

chrysophytes took over multiple tanks with UV in place.

Roger that. Neither of my tanks are showing any significant change at this point, but I will let them run a bit. The floss is certainly not collecting at the pace it was with ostreopsis but will let it run through this second light cycle to see if it picks up.

 

[ScottB]

Well it is a week later and I'd say the situation is unchanged. UV no noticeable impact. Filter floss, some accumulation perhaps, but I feel like it is more just catching what I am basting versus being an attractant.

Nutrient still the same 10/.1

I have a theory going but not sure how to prove/disprove or even correct but here goes... this stuff is feasting upon weakened, dead or dying coralline algae. I don't know that the stuff is predatory on coralline, or just scavenging. When I baste the rock, coralline comes often in a softened state. It is weird.

If I run with this theory, I'd want to boost the health of my coralline but cannot imagine yet what is missing. My SPS are ripping right now. My Triton ICP numbers are all nominal. But those were year end numbers, so I guess I should start there with an updated ICP. Thanks for allowing me to think this through with you.

 

[taricha]

I have a theory going but not sure how to prove/disprove or even correct but here goes... this stuff is feasting upon weakened, dead or dying coralline algae. I don't know that the stuff is predatory on coralline, or just scavenging. When I baste the rock, coralline comes often in a softened state. It is weird.

that's a really fascinating observation.

the thick gel may be changing the local rock chemistry in some way. I'm imagining it lowers pH, with lots of sugars and low gas exchange.

 

[ScottB]

that's a really fascinating observation.

the thick gel may be changing the local rock chemistry in some way. I'm imagining it lowers pH, with lots of sugars and low gas exchange.

Hmmm. Somebody around here described the same process in cyanobacteria mats. Low pH used to dissolve aragonite and capture carbohydrates for fuel. Which reminds me of something else.

Earlier in the winter, I had a little run with red cyano in there. Noisy nutrients and some new rock work kicked it off. From there, the balance of power shifted to these guys. (And NO, I did not use Chemiclean.)

So perhaps the cyano weakened the coralline and these guys are scavenging. It is a fair bit of work keeping up with them. Will be glad when it is over.

 

[taricha]

I'm fascinated by the large amounts of mucus this nuisance generates. It's such a strong jelly.
Wildly speculating here...
Because the mucus (EPS - "extracellular polymeric substance") is high in sugars (polysaccharides) and ought to be delicious to bacteria. So I'm guessing there's some antibacterial activity from the chrysophyte that keeps its luxurious home from being eaten.
I am generally skeptical of grunge eating bacterial products (Waste Away, Microbacter Clean, MB7 etc) but one of my skeptical points is that they are usually added in systems where the foods aren't rich enough to germinate the spores. This luxurious slime has plenty of sugars. I wonder if you sucked up hunks of the chrysophyte and put into beakers and tried microdoses of the bacterial products would any of them wake up and take advantage of the buffet?

The product descriptions make you think that they were all born to devour biofilms so maybe worth a try. Could fail if the polysaccharides aren't in a form that can penetrate to the germination site of the bacteria spores or if the antibacterial compounds from the chrysophyte keep the bacteria at bay.

 

[ScottB]

I'm fascinated by the large amounts of mucus this nuisance generates. It's such a strong jelly.
Wildly speculating here...
Because the mucus (EPS - "extracellular polymeric substance") is high in sugars (polysaccharides) and ought to be delicious to bacteria. So I'm guessing there's some antibacterial activity from the chrysophyte that keeps its luxurious home from being eaten.
I am generally skeptical of grunge eating bacterial products (Waste Away, Microbacter Clean, MB7 etc) but one of my skeptical points is that they are usually added in systems where the foods aren't rich enough to germinate the spores. This luxurious slime has plenty of sugars. I wonder if you sucked up hunks of the chrysophyte and put into beakers and tried microdoses of the bacterial products would any of them wake up and take advantage of the buffet?

The product descriptions make you think that they were all born to devour biofilms so maybe worth a try. Could fail if the polysaccharides aren't in a form that can penetrate to the germination site of the bacteria spores or if the antibacterial compounds from the chrysophyte keep the bacteria at bay.

"luxurious slime" Only you could come up with that one. Only you.

OK I am on it. I have a few bacteria products, beakers, and buckets of luxurious slime.

 

[ScottB]

Clamped a couple beakers to the inside glass. Will see how they do.

A "before" picture:

*Edit: The Control sample with no bacteria added.

 

[taricha]

Awesome. Also do one control beaker of chrysophytes that gets no bacterial additives just for comparison.

 

[ScottB]

Awesome. Also do one control beaker of chrysophytes that gets no bacterial additives just for comparison.

Doh! I always forget about the control. Thanks.

 

[ScottB]

Roughly 24 hours later... all three samples are now mostly floating and with air bubbles. Not much apparent differences I can note across the three samples. If anything, the control sample has diminished a tiny bit.

Samples are at tank temp and with light. Probably some salinity creep. I added a few ml of RODI now to compensate.

 

[saltyhog]

I have two small areas in my tank where I can get a sample of chrysophytes at any time. They look much like the ostreopsis I'm battling except for the color. When I sample this mucous it's a mono culture of chrysophytes. Elsewhere I have a dominant diatom bloom. I'm not optimistic about diatoms being the answer to chrysophytes at least in my case.

I could of sworn I read that their cell wall was constructed of silicates but that must not be true.