Diatoms - My "FACTS"

[pepedopolous]

I had diatoms until I added 10 Amano shrimp. It disappeared overnight!

 

[ian_m]

Ottos scoffed my diatoms when I first set the tank up.

Occasionally come back after major replanting and substrate fiddling.

 

[zanguli-ya-zamba]

I have been battling with diatom for long time.
Now my tank is diatome free lol.
I think for a new tank what really help is bio mass ! you need to add fast growing plants and a lot of it.
Second will be filter, you need to have a filter that is mature and have a good bacterial colony.
Water change a lot etc....
these three points have helped me a lot to end this battle. My substrate is plain sand, and I have not changed it. I have always had plain sand in my tanks.
I have not increase my lights so they are not related to this.
One other thing I have done is adding CO2 24/7 at low rate. Like 3 or 4 time less than what I was pumping when I had diatome.

I think that a mature tank and filter is really important, and it doesn't take 2 month to have a mature tank, it takes loooonger.

well sorry for such a confuse answer and explanation lol but i am in a hurry.

Now that I have won the battle on diatom, I have some BBA (first time) and BGA I am on it but I am living the country in 1 week for 25 days, so the story will continue in august lol

cheers.

 

[parotet]

IME (no objective measurements... just an opinion) diatoms don't care:

- about light (I have suffered them both in dark and bright areas) [it matches with scientific knowledge: algae need much less light than macrophytes and of course can do well high levels]
- about flow (I had them in the filter outflow and in stagnant areas)
- about ferts (I had them when dosing different ferts to no dosing) [it matches with scientific knowledge: algae can live with much less nutrients than macrophytes but of course benefit from high levels]
- silicates (at least, I have a clay based substrate very rich in diatoms… 🙁 and a sand one free of it)

IME they probably care:

- about organic matter build-up
- about poor filtration capacity due to small and/or immature filter (which at the end is the same: limitation to manage organic matter breakdown, ammonia, etc.)

As an example brown diatoms frequently appear in my nano tank (24 l) after re-scaping (ammonia, plant debris, etc.), breeding (less WC frequency, more frequent fish/fry feeding) or when my filter gets clogged (most of the times a consequence of re-scaping and breeding episodes).
I guess the difference with my larger tank (same WC frequency -twice a week if posible, always once a week-, same substrate disturbance, etc.) is that in my 60 liters tank I have an Eheim 2215 (significant filtration rate + high filter media surface + nearly impossible to get clogged in 1-2 month + quick recovery of denitrifying bacteria colony after cleaning). As a result in my 60 liters tank, which does not suffer from diatoms, I have a significant “safety margin” to address organic build-up without consequences. My nano tank has an internal filter with foam and a tiny box of bioballs (150 ml? probably less). I notice that this filter cannot get rid a debris excess. Being an internal filter, most of the debris remain attached to the foam and are not sucked by the filter (at least shrimps seem to enjoy it!). Another fact is that every time I clean the filter (even with tank water), it looks like it needs a week to work fine again (due to lesser bacteria surface?)

Well, my two cents…

Jordi

 

[sciencefiction]

Well, I stumbled across this article which may answer a few questions.

According to this article, diatoms apparently love organic compounds and utilize them heterotrophically, and also are also more efficient in low light levels.

http://www.luc.edu/media/lucedu/bio/tuchman/tuchman06.pdf

 

[NC10]

Nice find. I'll have a proper read later.

 

[Sacha]

Please review my posts in this thread:

http://www.ukaps.org/forum/index.php?threads/Whats-this-algae?.32517/

I've seen this on this forum a couple of times, and I have to put it right.

Diatoms' cell walls are made up of silica. Without available silica, they can't rebuild their cell walls, and they can't multiply.

Clive, you're a smart guy, I know these papers won't be beyond you.

http://www.ncbi.nlm.nih.gov/m/pubmed/16193051/

http://www.nature.com/nature/journal/v397/n6719/abs/397508a0.html

It's pretty clear that diatoms thrive on silica. The more silica there is, the faster they grow.

http://onlinelibrary.wiley.com/doi/...sCustomisedMessage=&userIsAuthenticated=false

"Diatom growth depends on silicate availability, in addition to nitrate and phosphate, but northern Atlantic waters are richer in nitrate than silicate. Following the spring stratification, diatoms are the first phytoplankton to bloom. Once silicate is exhausted, diatom blooms subside in a major export event. Here we show that, with nitrate still available for new production, the diatom bloom is prolonged where there is a periodic supply of new silicate: specifically, diatoms thrive by 'mining' deep-water silicate brought to the surface by an unstable ocean front"

"As diatoms have an absolute requirement for silicon (as silicic acid)3, its supply into the photic zone — largely by silica dissolution and upwelling — controls diatom production (and consequently the biological uptake of atmospheric CO2 by the ocean) over vast oceanic areas"

"Silicon is a major limiting nutrient for diatom growth and hence is a controlling factor in primary productivity."

There are loads of papers on exactly this subject, a quick Google brought these up.

 

[Sacha]

I don't really see how anyone can argue with that?

 

[sciencefiction]

Well, according to the above article, they metabolize heterotrophically without any silica but organics compounds.
We would all have diatoms if sand was to blame only.

 

[Sacha]

"As diatoms have an absolute requirement for silicon (as silicic acid) its supply into the photic zone — largely by silica dissolution and upwelling — controls diatom production (and consequently the biological uptake of atmospheric CO2 by the ocean) over vast oceanic areas"

"Silicon is a major limiting nutrient for diatom growth and hence is a controlling factor in primary productivity."


So you are saying this is wrong? Bear in mind it is published in nature journal

 

[sciencefiction]

"As diatoms have an absolute requirement for silicon (as silicic acid) its supply into the photic zone — largely by silica dissolution and upwelling — controls diatom production (and consequently the biological uptake of atmospheric CO2 by the ocean) over vast oceanic areas"

"Silicon is a major limiting nutrient for diatom growth and hence is a controlling factor in primary productivity."


So you are saying this is wrong? Bear in mind it is published in nature journal

No, I am not saying it's wrong. But maybe diatoms are not as simple and are similar to certain bacteria that can change metabolism and use different sources of food. Did you read the article I posted above?
Plus it may depend on species too. Most articles talk about the ocean where we are dealing with fresh water tanks.
Personally, with having 4 tanks with silica sand diatoms have never been a problem for me. Are you saying I should have had diatoms? But I can always trigger them by increasing the bioload all of a sudden.
Certainly the article says that in the dark they utilise the organics better up to 94% compared to 68% in light conditions

 

[Mr. Teapot]

I don't mind being a guinea pig in this debate… let me know your choice of silicon and I'll dump a bag of it in my filter and record what happens.

 

[Sacha]

I will read the article now.

One thing is for sure. All diatoms, no matter what species, will die if there is zero available silicates. That is because their cell walls are made up of silica compounds. It's well known that diatoms do better in darkness than they do in light. But just don't let Clive hear you say that (everyone else is wrong apparently).

 

[sciencefiction]

That is because their cell walls are made up of silica compounds

I can't argue about it as I haven't read the proper info expanding on this but lets take an example with shrimp who have copper based oxygen transport system (Hemocyanins) and copper is essential to their survival, yet high copper amounts kills them outright. And shrimp don't eat copper or depend on the amounts of copper to multiply and flourish, they just need some of it for survival.
So silicates for diatoms cell survival means just that.

 

[Sacha]

Silicon is a major limiting nutrient for diatom growth.

That is simple fact. I posted this before, Clive told me my "data were faulty". It's up to the OP who he believes..

 

[sciencefiction]

Silicon is a major limiting nutrient for diatom growth

The diatom species examined in this study all inhabit
benthic habitats where they may often
encounter light depletion due to frequent burial in
the sediments, highly turbid or stained overlying
water, or from high density algal mats. Under such
light-limited conditions these diatoms can activate
mechanisms for uptake and metabolism of organic
substrates as a survival strategy. In addition, they
have the ability to turn off these metabolically
costly uptake mechanisms when irradiance is
adequate for photosynthesis.
Comparable forms of

these compounds and their derivatives are present

in aquatic ecosystems and may be introduced into

the environment from a number of natural

sources, including decomposition, allochthonous

inputs, autochthonous inputs, animal or plant

excretions, or UV-B photodegradation of DOC

(Wetzel et al., 1995; De Lange et al., 2003).

In addition to using these compounds as a

source of carbon, diatoms might utilize amides,

amines, and amino acids as a source of nitrogen as

well. Diatoms readily take up dissolved organic

nitrogen in both benthic (e.g., Nilsson & Sundba・N ck,

1996) and planktonic habitats

 

[NC10]

Found this as well, just to add something else into the mix 😀


"If the silicate (Si) to phosphate (P) ratio is high, then diatoms are likely to have a growth advantage over true algae types and Cyanobacteria..................(when) phosphate is accumulating in the maturing tank, the Si: P ratio will change in favour of phosphate, which is likely to favour the growth of green algae instead."


I'm using Easylife Profito which doesn't have phosphates. I didn't need the phosphates due to my fish, or eventual fish. I'm guessing that a lot of the more "showy" high tech tanks with a few small fish (or none) would use a fert containing phosphate, obviously changing the ratio in favour of phosphate from the very beginning = no diatoms, ever, possibly.

As this is just a thought and not my actual factual "facts" I deserve a warning for derailing my own thread 😀 Interesting nevertheless.

 

[ceg4048]

Silicon is a major limiting nutrient for diatom growth.

That is simple fact. I posted this before, Clive told me my "data were faulty". It's up to the OP who he believes..

Readers are encouraged to believe the hobbyists who don't get diatoms in their tanks.
The "fact" is I don't get diatoms - unless I want them to appear.
Regret to advise that your data is still faulty.

Cheers,

 

[Sacha]

It's not my data, it's the data published in the journal of Phycology.

"Silicon is a major limiting nutrient for diatom growth"

That is a verbatim quote from the peer- reviewed paper

So are you telling me this peer- reviewed scientific data is faulty? If so, why not write a letter to the authors informing them that their research and findings are incorrect?

 

[Sacha]

Sorry, I am getting my papers mixed up. The paper I am referring to is entitled "SILICON METABOLISM IN DIATOMS: IMPLICATIONS FOR GROWTH", and was published in the journal of Phycology, volume 36, issue 5.

Clive, please read that paper. The entire paper is about how increased silicates means increased diatom growth.