Tank/Dino help

AquaSixAquaticsReef

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I believe I have a dinoflagellate outbreak in my tank. I have watched what BRS says to do to help with this problem (such as adding copepods, which I added 3 jars last week) , but I am wondering if there may be some more things to correct. After looking through some other threads, I plan to order some sodium silicate to dose into my tank, and I am running a Hygger UV light that is just sitting in the sump by the protein skimmer. It is only a 9-watt light; it is just what I had on hand. I am open to any recommendations on lights I can add to my sump that would not break the bank but would work much better for a 90-gallon tank with a 30-ish gallon sump. Recently, my tank bottomed out on phosphate, and I am wondering if that is what caused this outbreak. However, I want to make sure I am not doing anything else wrong. As of tonight, all of my tests showed the following:

Calcium 420
Phosphates .04
Nitrates 10
Alkalinity 8
Salinity 1.026
PH 8.0

Any help is appreciated! Thanks!
 
Zero phosphate would contribute to Dinoflagellets.

Maintaining phosphate concentration; adding pods & silicates are all good.

Depending on the type of Dinoflagellet determines if your UV is effective.

“I believe I have a dinoflagellate outbreak in my tank.”
Please provide full tank shot with white light.
 
Zero phosphate would contribute to Dinoflagellets.

Maintaining phosphate concentration; adding pods & silicates are all good.

Depending on the type of Dinoflagellet determines if your UV is effective.
I don’t have a microscope to determine. I’ve kinda just narrowed it down by what’s happening in my tank. All of my snails, except my conch and a large turbo, have died/disappeared. Another thing I’ve noticed is all of the bubbles where it’s at, rocks and sand, but I don’t know if that helps classify it.
 

Here’s a video from the other day of the sand. The main difference of today is there is a ton of bubbles on the sand now. My lights have been off tonight so I don’t have a full white light picture but I could get one tomorrow.
 
I don’t have a microscope to determine. I’ve kinda just narrowed it down by what’s happening in my tank. All of my snails, except my conch and a large turbo, have died/disappeared. Another thing I’ve noticed is all of the bubbles where it’s at, rocks and sand, but I don’t know if that helps classify it.
Those symptoms indicate Dinoflagellets.
 
I don’t have a microscope to determine. I’ve kinda just narrowed it down by what’s happening in my tank. All of my snails, except my conch and a large turbo, have died/disappeared. Another thing I’ve noticed is all of the bubbles where it’s at, rocks and sand, but I don’t know if that helps classify it.
Those symptoms indicate Dinoflagellets.
I figured if I take the approach of the silicates and a UV I would be attacking multiple strands. But I’m unsure what UV light to get, one with a pump vs just a light that sits in the sump.
 
I figured if I take the approach of the silicates and a UV I would be attacking multiple strands. But I’m unsure what UV light to get, one with a pump vs just a light that sits in the sump.
I thought that you already had a 9W UV sterilizer that sits in a 30G sump and I don’t think that is effective.

If you want to address mobile Dinoflagellets with a proper UV and pump, you will likely spend between $200-$300. I would expect 30W to be minimum size to get.
 
I figured if I take the approach of the silicates and a UV I would be attacking multiple strands. But I’m unsure what UV light to get, one with a pump vs just a light that sits in the sump.
I thought that you already had a 9W UV sterilizer that sits in a 30G sump and I don’t think that is effective.

If you want to address mobile Dinoflagellets with a proper UV and pump, you will likely spend between $200-$300. I would expect 30W to be minimum size to get.
“If you want to address mobile Dinoflagellets with a proper UV and pump, you will likely spend between $200-$300. I would expect 30W to be minimum size to get.”

This is what advice I was looking for. I assumed my little 9 watt is doing nothing but I had no idea what size to even look for. Thanks!
 
Upon further thought, I was curious as to why copepods were not effected by toxins from Dinoflagellets so I googled it.

  • “Resource Competition.”


    “Copepods—especially benthic varieties like Tisbe, Tigriopus, and Apocyclops—compete with dinoflagellates for space and nutrients while consuming non-toxic biofilms and microalgae.
  • Direct Grazing. Some hardy copepods will actively eat certain nuisance dinoflagellates (such as Amphidinium or Prorocentrum), whereas snails will succumb to the toxins.
  • Best Practices. Because starving copepods are more likely to be poisoned by forced ingestion, reef keepers typically dose live phytoplankton alongside copepods. This gives the copepods a safe, nutritious food source so their population can multiply and outcompete the dinoflagellates. [1, 2, 3, 4, 5, 6, 7]”

Then, I googled amphipods:

AI Overview


Amphipods generally tolerate dinoflagellates much better than snails do, and they are not typically killed by the neurotoxins or chemical defenses that wipe out gastropods. [1, 2]

How Amphipods React to Dinoflagellates
    • Higher Resilience: Unlike snails—which actively graze on surfaces covered in toxic dinoflagellates (like Ostreopsis or Amphidinium) and ingest lethal doses of compounds like okadaic acid—amphipods tend to be much hardier against these microalgae. [1, 2, 3]
    • Dietary Limitations: Most standard copepods and amphipods do not actively consume or clear out heavy dinoflagellate blooms. While they might scavenge detritus or film in the tank, they rarely use dinoflagellates as a primary food source. [1]
    • Survival During Outbreaks: During a severe dinoflagellate crash where cleanup crew snails die off en masse, amphipod populations will often survive, though they may suffer if water quality plummets or if free-floating toxins spike heavily in the water column. [1, 2]
 
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Upon further thought, I was curious as to why copepods were not effected by toxins from Dinoflagellets so I googled it.

  • Resource Competition.


    Copepods—especially benthic varieties like Tisbe, Tigriopus, and Apocyclops—compete with dinoflagellates for space and nutrients while consuming non-toxic biofilms and microalgae.
  • Direct Grazing. Some hardy copepods will actively eat certain nuisance dinoflagellates (such as Amphidinium or Prorocentrum), whereas snails will succumb to the toxins.
  • Best Practices. Because starving copepods are more likely to be poisoned by forced ingestion, reef keepers typically dose live phytoplankton alongside copepods. This gives the copepods a safe, nutritious food source so their population can multiply and outcompete the dinoflagellates. [1, 2, 3, 4, 5, 6, 7]
I have been feeding OceanMagik daily for the copepods so hopefully that’s just been feeding them. I’m obviously trying to clear this up fast so I’m ordering anything to help by tomorrow at the latest.
 
Consider using activated carbon to remove DOC (Dissolved Organic Carbon). I recently read in a r2r thread that zero phosphate and high DOC contributes to Dinoflagellet infestation.
 
You're seeing signs of toxins, so please read this:
https://www.reef2reef.com/threads/dinoflagellates-–-are-you-tired-of-battling-altogether.293318/

There are LOTS of posts (>10K) from folks who've already gotten their tanks fixed but you mainly need to read just the first post.

You can surf the comments or run a search on the thread to see what kinds of UV people have set up.

If you get a microscope, you can post an image of your dino's there for ID.....ANY microscope will work, even a $15 toy scope like I started out with, but a $40 scope made of metal will be much better. A high end scope with advanced features is NOT required.

This thread goes nicely with the first one:
https://www.reef2reef.com/threads/selecting-a-microscope.308826/

Advance hint: Adding some activated carbon will take the edge off the toxins....use 1/4 normal dose and change it weekly instead of monthly. Dosing some phosphate to 0.10 ppm ASAP to limit damage to corals. Maintain that level daily until things normalize. ≥0.10 ppm PO4 and ≥5.0 ppm NO3 should be your targets.
 

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