Are these diatoms?

shawtygotbass

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Does this algae look like diatoms? It’s brown, kind of hairy/stringy.

I have been dealing with this algae and haven’t been able to beat it, even though my nutrients are good (1 to 4 ppm nitrate, .02 to .08 ppm phosphate).

I recently found out my RODI water has 4ppm of silicates.

So my 25% weekly water changes essentially increase my silicates to 1ppm. I already ordered two additional DI attachments, one being an anion target to address the silicates.

I’m just hoping these are diatoms so I finally found the issue I’ve been dealing with for so long.

IMG_1368.png IMG_1364.jpeg IMG_1360.jpeg IMG_1358.jpeg
 

david.kint17

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Its hard to tell from your pictures but I think its just hair algae. How old is your system?
 

Isaac Alves

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Hmmm…hairy and stringy is not how I would characterize the visual appearance of a diatom bloom.

I look for a rusty brown dusting or powder’y appearance. Easiest to see on the sand bed.

It’s hard for me to tell from the pictures, I’m sorry.

Good excuse to get a microscope 😅
 
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shawtygotbass

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It looks like some type of algae in the first picture and Dinos in the sand.
Okay that’s what I thought. I’m just so confused how the algae keeps growing when my nutrients have never been out of whack. Can hairy algae also thrive with silicates, or does that only feed diatoms?

And the hermits eat the stuff on the sand. Do they eat Dinos?
 

Isaac Alves

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I believe dinoflagellates have no predatory competition. They can only be outcompeted for space in your tank’s entertainment.


As opposed to diatoms which are consumed by various organisms.
 

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Okay that’s what I thought. I’m just so confused how the algae keeps growing when my nutrients have never been out of whack. Can hairy algae also thrive with silicates, or does that only feed diatoms?

And the hermits eat the stuff on the sand. Do they eat Dinos?
I’m sorry I don’t know if silicate feeds algae. Never heard of it though. Hermits aren’t supposed to eat Dino’s as far as I know. Do you have a microscope to determine if it really is Dino’s, or maybe your LFS does ?

I believe dinoflagellates have no predatory competition. They can only be outcompeted for space in your tank’s entertainment.


As opposed to diatoms which are consumed by various organisms.
Some pods are known to eat them. Thats why it’s recommended to add some when fighting Dino’s.
 
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shawtygotbass

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I believe dinoflagellates have no predatory competition. They can only be outcompeted for space in your tank’s entertainment.


As opposed to diatoms which are consumed by various organisms.
Okay I see.
I’m sorry I don’t know if silicate feeds algae. Never heard of it though. Hermits aren’t supposed to eat Dino’s as far as I know. Do you have a microscope to determine if it really is Dino’s, or maybe your LFS does ?


Some pods are known to eat them. Thats why it’s recommended to add some when fighting Dino’s.
I can order a microscope to check from Amazon.

Dinos would be interesting because this tank always ran on slightly higher nutrient levels, not HIGH, just never bottomed out.

I always had that brown stuff on the sandbed, even when I was .08 to .1+ phosphate and 5+ nitrate. I really just dialed in the nutrients in the last month by installing a skimmer, being more diligent about filter socks, and weekly instead of every 2 week water changes.

That said, I had a massive turbo snail die while I was out of town for two days and it spiked my nitrate from like 2ish to 12. I just checked my water just now. That snail must have died right when I left because it was moving right before I walked out then door!

Nitrate is currently 12 and phosphate is .06. And that sand picture was taken a couple hours ago.
 

mcarroll

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Okay that’s what I thought. I’m just so confused how the algae keeps growing when my nutrients have never been out of whack. Can hairy algae also thrive with silicates, or does that only feed diatoms?
Algae growth isn 't correlated to nutrient levels like the internet tells you it is.

"high" doesn't mean you get algae growth and "low" neither prevents it nor makes it go away.

Cleanup crew is what provides control – in the wild AND in reef tanks. (You are cleanup crew member #1 at the top of the pyramid.)

And the hermits eat the stuff on the sand. Do they eat Dinos?
Hermits are fairly useless vs algae even if they eat some of it. They are excellent scavengers.

Focus on herbivorous snails: Turbo, Astrea, Trochus, Margharita, etc.

IMO the stuff on the sand looks more like cyanobacteria. Also more consistent with nutrient levels you're reporting.

A microscope is nice and I recommend having one, but IMO you can do a "shake test" to find out what you need to know at this point.

Get a sample of the algae in a container. Aggressively shake up the sample until it's broken into smithereens. Then place the sample under your lights for a while and see if any of the pieces gather back into a mass. Only dino's will move like that.

That said, I had a massive turbo snail die while I was out of town for two days and it spiked my nitrate from like 2ish to 12. I just checked my water just now. That snail must have died right when I left because it was moving right before I walked out then door!

Nitrate is currently 12 and phosphate is .06. And that sand picture was taken a couple hours ago.
Nitrates of 2 isn't high, BTW.....that's essentially 0.00 when you consider the accuracy of our testing equipment.

Current numbers are better – but they have to be consistent (or higher) and not periodically bottoming out (eg with water changes, etc).
 
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shawtygotbass

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Algae growth isn 't correlated to nutrient levels like the internet tells you it is.

"high" doesn't mean you get algae growth and "low" neither prevents it nor makes it go away.

Cleanup crew is what provides control – in the wild AND in reef tanks. (You are cleanup crew member #1 at the top of the pyramid.)


Hermits are fairly useless vs algae even if they eat some of it. They are excellent scavengers.

Focus on herbivorous snails: Turbo, Astrea, Trochus, Margharita, etc.

IMO the stuff on the sand looks more like cyanobacteria. Also more consistent with nutrient levels you're reporting.

A microscope is nice and I recommend having one, but IMO you can do a "shake test" to find out what you need to know at this point.

Get a sample of the algae in a container. Aggressively shake up the sample until it's broken into smithereens. Then place the sample under your lights for a while and see if any of the pieces gather back into a mass. Only dino's will move like that.


Nitrates of 2 isn't high, BTW.....that's essentially 0.00 when you consider the accuracy of our testing equipment.

Current numbers are better – but they have to be consistent (or higher) and not periodically bottoming out (eg with water changes, etc).
I did the coffee filter test. This is it after 45 min. Is this Dino’s?
 

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mcarroll

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Are you calling the shake test the coffee filter test, or is that something different? If you do the shake test, then you are the one telling me if it's dino's or not. :)

(Tell me what the coffee filter test is if it's something else.)
 
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shawtygotbass

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Are you calling the shake test the coffee filter test, or is that something different? If you do the shake test, then you are the one telling me if it's dino's or not. :)

(Tell me what the coffee filter test is if it's something else.)
I scraped some of the gunk out of the tank with tank water, shook really hard for 30 seconds, then poured through a coffee filter into the cup.

Then I put the cup under a light for 45 min.
 

Mr. Mojo Rising

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The algae on the rocks looks like green hair algae to me. On the sand it looks like possibly cyano or dino's, but not sure. Algae consumes nutrients very fast, so you can't really trust your test kits when you have a bad algae problem IMO
 

Idech

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Dinos would be interesting because this tank always ran on slightly higher nutrient levels, not HIGH, just never bottomed out.
I’ve had Dino’s for 4 years on and off with high nutrients. Biological imbalance brings them on and if there is no competition and fuel, they thrive.
 
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shawtygotbass

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The algae on the rocks looks like green hair algae to me. On the sand it looks like possibly cyano or dino's, but not sure. Algae consumes nutrients very fast, so you can't really trust your test kits when you have a bad algae problem IMO
I ordered a microscope to confirm if it’s dinos. I’m thinking it might be, because a couple of my corals have been struggling.

Bought a UV sterilizer as well in case. Will start using it reguardless.

And I think you’re right. This tank nutrient levels have always read low-ish, but I’m not sure I have a true baseline yet. I have yet to fully clean it up since starting it last March, so I need to get this algae and potentially dinos in check then can better understand.
 
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shawtygotbass

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I’ve had Dino’s for 4 years on and off with high nutrients. Biological imbalance brings them on and if there is no competition and fuel, they thrive.
I have heaviest algae on the rocks and stuff.

Is it possible to only have dinos in sand, and none on rocks?
 

mcarroll

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Dinos would be interesting because this tank always ran on slightly higher nutrient levels, not HIGH, just never bottomed out.
Wait a minit.....

I scraped some of the gunk out of the tank with tank water, shook really hard for 30 seconds, then poured through a coffee filter into the cup.

Then I put the cup under a light for 45 min.
Maybe re-do the test without the coffee filter?

Did anything seem to move/regroup from the time you placed the sample under the light?

I ordered a microscope to confirm if it’s dinos. I’m thinking it might be, because a couple of my corals have been struggling.

Bought a UV sterilizer as well in case. Will start using it reguardless.

And I think you’re right. This tank nutrient levels have always read low-ish,
...which history is true?? Low? Or high?

I have heaviest algae on the rocks and stuff.

Is it possible to only have dinos in sand, and none on rocks?
It's unusual to have other stuff AND dino's....a dino bloom is usually very successful at killing off everything else in the tank. Since you seem to have at least green hair algae AND this other algae, I'm guessing not dino's.

But it occasionally happens that someone will get dino's in an otherwise normal-seeming tank....but never a full-on bloom.

As long as you're growing plenty of other stuff (eg green algae), just continue stabilizing the tank and doing what you can to add diversity....new amphipods and copepods, etc can help a little. Siphon out or hand-remove as much algae as you can as often as you can – regardless of the algae type. (Siphoning into a low-micon filter sock lets you put the water back in the tank after siphoning. Use <50µ....something closer to 5µ or 10µ would be more ideal.)

If it does turn out to be dino's and the tank trends more toward an outbreak, then make sure you've read the first page on my dino thread and get started with the info there:
Dinoflagellates – Are You Tired Of Battling Altogether?
 

mcarroll

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Dinos would be interesting because this tank always ran on slightly higher nutrient levels, not HIGH, just never bottomed out.
Wait a minit.....

I scraped some of the gunk out of the tank with tank water, shook really hard for 30 seconds, then poured through a coffee filter into the cup.

Then I put the cup under a light for 45 min.
Maybe re-do the test without the coffee filter? I don't even drink coffee. ;)

Did anything seem to move/regroup from the time you placed the sample under the light?

And I think you’re right. This tank nutrient levels have always read low-ish,
...which nutrient history is true?? Low? Or high like you mentioned earlier?

I have heaviest algae on the rocks and stuff.

Is it possible to only have dinos in sand, and none on rocks?
It's unusual to have other algae AND dino's. A dino bloom is usually very successful at killing off everything else in the tank. Since you seem to have at least green hair algae AND this other algae, I'm guessing not dino's.

But it occasionally happens that someone will get dino's in an otherwise normal-seeming tank....but never a full-on bloom.

As long as you're growing plenty of other stuff (eg green algae), just continue stabilizing the tank and doing what you can to add diversity....new amphipods and copepods, etc can help a little. Siphon out or hand-remove as much algae as you can as often as you can – regardless of the algae type. (Siphoning into a low-micon filter sock lets you put the water back in the tank after siphoning. Use <50µ....something closer to 5µ or 10µ would be more ideal.)

If it does turn out to be dino's and the tank trends more toward an outbreak, then make sure you've read the first page on my dino thread and get started with the info there:
Dinoflagellates – Are You Tired Of Battling Altogether?
 
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shawtygotbass

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Wait a minit.....


Maybe re-do the test without the coffee filter? I don't even drink coffee. ;)

Did anything seem to move/regroup from the time you placed the sample under the light?


...which nutrient history is true?? Low? Or high like you mentioned earlier?


It's unusual to have other algae AND dino's. A dino bloom is usually very successful at killing off everything else in the tank. Since you seem to have at least green hair algae AND this other algae, I'm guessing not dino's.

But it occasionally happens that someone will get dino's in an otherwise normal-seeming tank....but never a full-on bloom.

As long as you're growing plenty of other stuff (eg green algae), just continue stabilizing the tank and doing what you can to add diversity....new amphipods and copepods, etc can help a little. Siphon out or hand-remove as much algae as you can as often as you can – regardless of the algae type. (Siphoning into a low-micon filter sock lets you put the water back in the tank after siphoning. Use <50µ....something closer to 5µ or 10µ would be more ideal.)

If it does turn out to be dino's and the tank trends more toward an outbreak, then make sure you've read the first page on my dino thread and get started with the info there:
Dinoflagellates – Are You Tired Of Battling Altogether?
Sorry, I meant I think I’ve always had a hard time getting an accurate nutrient reading because there has always been more than desired algae present. So even though I was reading say 5 nitrate and .08 phosphate, wouldn’t that reading as a baseline be skewed as it’s “artificially pulled down” from the excess algae?

I guess what I’m saying is I’ve never seen 25 nitrate and .2+ phosphate or something like that, but I’m wondering if it’s the algae that kept me reading lower.

And regarding dinos, that’s good news. Hopefully it’s just cyano or something. I have a microscope coming in shortly, so I’ll confirm and message back.
 

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