Diatom "Algae" and Black Diamond Blasting Sand

[Fish Folk]

Ok. I'll admit it: I'm a penny-pinchin' "save a buck" kind of NERM. When we built a three-tank aquarium rack back a few years, my son and I decided to go for black diamond blasting sand. The stuff was inexpensive, and it got enough good reviews that we figured it would be worth it. We rinsed it out thoroughly, smoothing off my fingers and leaving nasty gray stains in our basement tub for a long while. And we've kept hundreds of fish in these tanks now very successfully.

We've managed to get some plants to root in it. We've added crushed coral in several tanks with BDBS to increase water hardness as well. But one continual disappointment has been a profusion of brown algae / diatom "algae." From what I've been learning, Diatoms feed on SiO2 (silicon dioxide). From a published analysis of its chemical composition, BDBS is at least 40% SiO2.

I've noticed that cold water tanks are less prone to brown algae. What has been your experience?

[Fish Folk]

Here are a couple photos of chronic diatom in tanks with BDBS…

on the wood:

On the Hygro leaves:

[Vanish]

I haven't experienced this in my 90g (tropical) with BDBS, but I am also doing weekly 50% water changes on it.

Your photos looks "fuzzier" than what I usually see with diatoms.

[HH Morant]

I have a new tank in which I am using coal slag blasting media (same as BDBS). All I could find in the stores was medium grit, so I ordered online (and paid more) to get coarse media because I like the way it looks.

My tank has not been set up long enough to show the algae problem you describe. I will be watching this thread to learn how to deal with it.

[Struggle]

I use BDBS on everything except for Caridina tanks and get diatoms when I set up a new tank. I just assumed it was new tank syndrome as it goes away after awhile. 

[HH Morant]

On 1/12/2022 at 11:48 AM, Struggle said:

I use BDBS on everything except for Caridina tanks and get diatoms when I set up a new tank. I just assumed it was new tank syndrome as it goes away after awhile. 

Thanks for the information, @Struggle. How soon does the diatom algae show up and about how long does it take to go away?

[Blaha]

I'm dealing that in my tank with standard gravel too. It's annoying because I cannot defeat it, but to a point it adds a more natural environment look to it. I'm fine with a compromise of only 75% victory compare to what it used to be like

 

[Ambush0908]

I used BDBS when I went to a bigger tank about 8 months ago,   I didn’t notice any diatom issue.  I have also had success with root plants using root tabs.  Like you I based the decision on a lot of positive posts online.  So far I think it was a great choice. 

[L_goodei200]

I personally don't think the black diamond blasting sand is the sole cause of your brown diatom algae problem, since:

1:  most common aquarium sand/gravel is quartz, which has the chemical formula SiO2 (aka, silicone dioxide) 

2: glass is also composed mainly of SiO2 

3: I personally haven't seen any difference in the amount of brown diatom algae in my tanks with and without BDBS

4: (this one I'm less sure about) I assume that BDA pulls its nutrients, including SiO2, from the water. And, as far as I know, BDBS doesn't leach much SiO2 into the water

[OnlyGenusCaps]

On 1/12/2022 at 6:14 AM, Fish Folk said:

Diatoms feed on SiO2

Diatoms do "consume" silicon to make their shells (frustule), but strictly speaking they don't feed on it.  It can be a major limiting factor in ocean systems in the end of diatom blooms though, so it can be limiting for their growth.  Thus, in situation where we have provided an effectively unlimited supply, this limitation could be removed and may allow them to stick around longer under certain circumstances.  I know I have them last in pool filter sand tanks with little light, and I am trying to keep them as part of the look in my P-Salt tank.  So, I think you could be completely correct that substrate can maintain them long-term. 

On 1/12/2022 at 6:51 AM, Fish Folk said:

Here are a couple photos of chronic diatom in tanks

I have to agree with some other folks in that the photos you posted don't look much like diatom algae to me.  I think of it as more of a brown varnish on surfaces.  You do have some interesting things growing in there though!!! 

[Fish Folk]

On 1/12/2022 at 8:22 PM, OnlyGenusCaps said:

Diatoms do "consume" silicon to make their shells (frustule), but strictly speaking they don't feed on it.  It can be a major limiting factor in ocean systems in the end of diatom blooms though, so it can be limiting for their growth.  Thus, in situation where we have provided an effectively unlimited supply, this limitation could be removed and may allow them to stick around longer under certain circumstances.  I know I have them last in pool filter sand tanks with little light, and I am trying to keep them as part of the look in my P-Salt tank.  So, I think you could be completely correct that substrate can maintain them long-term. 

I have to agree with some other folks in that the photos you posted don't look much like diatom algae to me.  I think of it as more of a brown varnish on surfaces.  You do have some interesting things growing in there though!!! 

Thanks… maybe my issue isn’t diatom at all??!! I’d love to learn what it is…

[Isaac M]

@Fish Folk I had a old 55 gallon set up for 2 years with black diamond blasting sand and I did not have much issue with diatoms, more with black beard algae. What is kind of ironic is that I have 2 aquariums with pool filter sand yet the aquarium that grows the most diatom/ brown algae is my 10 gallon with just normal gravel and dragon stone. From looking at the pictures, it looks more like mulm/ debris caught in some sort of biofilm like what I have in my current 55 gallon but I have no idea to be honest. Just throwing what I have experienced out there. 

[Fish Folk]

On 1/12/2022 at 9:12 PM, Isaac M said:

@Fish Folk I had a old 55 gallon set up for 2 years with black diamond blasting sand and I did not have much issue with diatoms, more with black beard algae. What is kind of ironic is that I have 2 aquariums with pool filter sand yet the aquarium that grows the most diatom/ brown algae is my 10 gallon with just normal gravel and dragon stone. From looking at the pictures, it looks more like mulm/ debris caught in some sort of biofilm like what I have in my current 55 gallon but I have no idea to be honest. Just throwing what I have experienced out there. 

Boom! That's my junk! Anyone got a conferring / contrasting thought on what this is? 

[OnlyGenusCaps]

On 1/12/2022 at 8:38 PM, Fish Folk said:

Anyone got a conferring / contrasting thought on what this is?

I'll second @Isaac M.

[Fish Folk]

On 1/12/2022 at 9:47 PM, OnlyGenusCaps said:

I'll second @Isaac M.

Any ideas how to work on getting rid of it? Causes? 

[OnlyGenusCaps]

I mean the mulm is just build up.  But I'm real confident you already know that, so that's not really the issue.  The biofilm...  Well, that can be caused by a lot of organisms.  My first pass would be to spot treat a section with H2O2 and note what the reaction is.  Does it bubble (more so than other stuff)?  Does it change color in a few hours or over night?  Does it disappear overnight or in a couple days?  Does it come off easily before or after treatment?  Basically what I am trying to figure out is whether it is a living matrix or an entirely excreted one, and then whether the treatment kills the organisms creating the biofilm.  If it kills it and it disappears, you have and answer of possible treatment.  If not, then some thinking about conditions might be in order.  But the H2O2 info would help with that too. 

[Randall from Texas]

On 1/12/2022 at 8:12 PM, Isaac M said:

@Fish Folk I had a old 55 gallon set up for 2 years with black diamond blasting sand and I did not have much issue with diatoms, more with black beard algae. What is kind of ironic is that I have 2 aquariums with pool filter sand yet the aquarium that grows the most diatom/ brown algae is my 10 gallon with just normal gravel and dragon stone. From looking at the pictures, it looks more like mulm/ debris caught in some sort of biofilm like what I have in my current 55 gallon but I have no idea to be honest. Just throwing what I have experienced out there. 

I will confirm the black beard algea in my high energy 100. I'm keeping discus and it's been a struggle from day one. 1.5 years in. About 80 lbs bdbs.

[Isaac M]

@Fish Folk I am just thinking out loud here but I suspect it has something to do with the decomposition of driftwood as I do not really have this issue in aquariums without driftwood.

However, in my 40 gallon the driftwood does not have that issue and it came from the same place as the driftwood in the 55 gallon. Two things that come to mind is that it has red cherry shrimp that spend their time eating biofilm and it also has better water flow. 

So my thoughts are either:

-No driftwood

-Add plecos or red cherry or any organism that will clean/ eat the driftwood

-Increase water flow so mulm does not settle and accumulate on the driftwood 

 

These thoughts however do not really explain the issue or attempt to truly understand the problem like what @OnlyGenusCaps proposed. 
 

@Randall from Texas, I had some black beard algae but it was not a crazy amount. But mine was not as high energy as yours as I imagine you have co2 and I did not. I had a decently bright light and organic soil under the bdbs. Here are 3 pictures of it taken from January 5, 2020 to November 6, 2020, it was rescaped once in that time frame:

I have always had issues with bba though, I just let it be at this point, the only thing I would try now are siamese algae eaters haha 

[Seattle_Aquarist]

Hi @Fish Folk

I have tanks where I use HTH Pool Filter Sand which is >99% silicon dioxide.  I like the nice white color and the fact that it has no pieces of shell or coral which can effect my pH and hardness (both dKH and dGH).  I have no problems with diatoms in those tanks.  Why?  Earlier in my experiences with planted tanks I did have diatom problems.  I had diatoms with plain, inert grave.  I had diatoms with calcined clay.  Then I found how to control diatoms, Otocinclus catfish.  I use Otocinclus affinis - one per every 10 -20 gallons and my diatoms disappear in a couple of weeks.  Once the diatoms are gone I feed the Otos an algae wafer once a week if they start looking skinny.  I drop the wafer in just before lights out because Otos are nocturnal.  You typically won't see them working during the day, they do most of the clean-up at night.  Below is by 75 gallon red spot green discus tank with HTH Pool Filter Sand.....no diatoms.  -Roy

[Fish Folk]

On 1/12/2022 at 10:43 PM, Seattle_Aquarist said:

Hi @Fish Folk

I have tanks where I use HTH Pool Filter Sand which is >99% silicon dioxide.  I like the nice white color and the fact that it has no pieces of shell or coral which can effect my pH and hardness (both dKH and dGH).  I have no problems with diatoms in those tanks.  Why?  Earlier in my experiences with planted tanks I did have diatom problems.  I had diatoms with plain, inert grave.  I had diatoms with calcined clay.  Then I found how to control diatoms, Otocinclus catfish.  I use Otocinclus affinis - one per every 10 -20 gallons and my diatoms disappear in a couple of weeks.  Once the diatoms are gone I feed the Otos an algae wafer once a week if they start looking skinny.  I drop the wafer in just before lights out because Otos are nocturnal.  You typically won't see them working during the day, they do most of the clean-up at night.  Below is by 75 gallon red spot green discus tank with HTH Pool Filter Sand.....no diatoms.  -Roy

Looks lovely! Thanks for sharing. This is really interesting. I am not certain that my problem is diatoms, now that others have shared their feedback. I'm going to wrestle with it using several techniques, and see how things develop. 

On 1/12/2022 at 10:37 PM, Isaac M said:

@Fish Folk I am just thinking out loud here but I suspect it has something to do with the decomposition of driftwood as I do not really have this issue in aquariums without driftwood.

However, in my 40 gallon the driftwood does not have that issue and it came from the same place as the driftwood in the 55 gallon. Two things that come to mind is that it has red cherry shrimp that spend their time eating biofilm and it also has better water flow. 

So my thoughts are either:

-No driftwood

-Add plecos or red cherry or any organism that will clean/ eat the driftwood

-Increase water flow so mulm does not settle and accumulate on the driftwood 

 

These thoughts however do not really explain the issue or attempt to truly understand the problem like what @OnlyGenusCaps proposed. 
 

@Randall from Texas, I had some black beard algae but it was not a crazy amount. But mine was not as high energy as yours as I imagine you have co2 and I did not. I had a decently bright light and organic soil under the bdbs. Here are 3 pictures of it taken from January 5, 2020 to November 6, 2020, it was rescaped once in that time frame:

I have always had issues with bba though, I just let it be at this point, the only thing I would try now are siamese algae eaters haha 

Awesome looking aquariums!

[Randall from Texas]

On 1/12/2022 at 9:37 PM, Isaac M said:

@Fish Folk I am just thinking out loud here but I suspect it has something to do with the decomposition of driftwood as I do not really have this issue in aquariums without driftwood.

However, in my 40 gallon the driftwood does not have that issue and it came from the same place as the driftwood in the 55 gallon. Two things that come to mind is that it has red cherry shrimp that spend their time eating biofilm and it also has better water flow. 

So my thoughts are either:

-No driftwood

-Add plecos or red cherry or any organism that will clean/ eat the driftwood

-Increase water flow so mulm does not settle and accumulate on the driftwood 

 

These thoughts however do not really explain the issue or attempt to truly understand the problem like what @OnlyGenusCaps proposed. 
 

@Randall from Texas, I had some black beard algae but it was not a crazy amount. But mine was not as high energy as yours as I imagine you have co2 and I did not. I had a decently bright light and organic soil under the bdbs. Here are 3 pictures of it taken from January 5, 2020 to November 6, 2020, it was rescaped once in that time frame:

I have always had issues with bba though, I just let it be at this point, the only thing I would try now are siamese algae eaters haha 

 

On 1/12/2022 at 9:43 PM, Seattle_Aquarist said:

Hi @Fish Folk

I have tanks where I use HTH Pool Filter Sand which is >99% silicon dioxide.  I like the nice white color and the fact that it has no pieces of shell or coral which can effect my pH and hardness (both dKH and dGH).  I have no problems with diatoms in those tanks.  Why?  Earlier in my experiences with planted tanks I did have diatom problems.  I had diatoms with plain, inert grave.  I had diatoms with calcined clay.  Then I found how to control diatoms, Otocinclus catfish.  I use Otocinclus affinis - one per every 10 -20 gallons and my diatoms disappear in a couple of weeks.  Once the diatoms are gone I feed the Otos an algae wafer once a week if they start looking skinny.  I drop the wafer in just before lights out because Otos are nocturnal.  You typically won't see them working during the day, they do most of the clean-up at night.  Below is by 75 gallon red spot green discus tank with HTH Pool Filter Sand.....no diatoms.  -Roy

I'm up to 6 hrs full blast fluval plant 3 and about to add a 2nd (or the coop). I am managing the bba. It looks natural. 

 

I also have a single Fat Oto cat, 1 blue eye lemon. Catfish are awesome.

[Struggle]

On 1/12/2022 at 12:10 PM, HH Morant said:

Thanks for the information, @Struggle. How soon does the diatom algae show up and about how long does it take to go away?

It usually begins at the two week mark and lasts a few months depending on how heavy I’m feeding.