Jump to content

Diatoms in my tank & Silicate test results...


Recommended Posts

  • Regular Member

So, my main tank (actually, every cycled tank I've owned) has always had a diatom problem.

 

I clean the diatoms, and they'll be back within few days.

 

Until recently, I just thought of it as "brown algae", and didn't give it a second thought; goldfish produce nitrates, algae eats nitrates so mystery solved...  

 

Then I read a few posts here on kokosgoldfish where people mentioned diatoms and I thought "what the bleep is a diatom?".

 

Most articles I've read mention that they show up in a recently established tank, and then tend to go away, sometimes taking weeks or even months.

Well, mine have never gone away, over several years. Something's not right, and the arrow seems to be pointing at me...

 

So, I read about diatoms, and found that high silicate levels in the water are a possible cause. I have pretty hard water, so I figured I'd get a test kit & see what my water actually has.  I used the Seachem MultiTest: Silicate test kit.

 

My tank's water tests to about 5 mg/L.  My tap water is identical. The test's literature mentions that freshwater typically has 0.25 mg/L. So it seems I have a pretty high silicate content in my tap water.

 

The Seachem test has a 'standard' sample of 6 mg/L you can use should you not trust your results. Fortunately, when I tested the standard, it is indeed 6 mg/L.

 

So, I have a few questions I'd like to know more about:

 

  • Other than chemical filtration (like PhosGuard), how can silicates (and diatoms) be mitigated?  (Or is it a losing battle, given the silicate levels in my tap water?)
  • I'd like to plant my tank (actually, I've started with simple ones like Anubais, Amazon Sword, and Water Wisteria).  The problem is the diatoms like to cover the leaves, and kill the plants
  • Other than being unsightly, are there any significantly negative things for my fish's health with diatoms in an aquarium?  (They're obviously bad for my plants.

Obviously, I want to do what's best for my fish, and it seems to me that diatoms aren't in their best interest. What else can I do to mitigate their presence?

Link to comment
Share on other sites

  • Regular Member

Since diatoms do not harm the fish, I'm always hesitant to take measures to prevent it.  Typically, my tanks have at different times developed diatoms.  At one point, the brown stuff did - if not kill the plant (I had only one) - covered the leaves and stems to such an extent that it didn't look green at all.  

 

At other times, I do not have diatoms at all - or nearly at all.  I do notice fewer diatoms in the tank when I have more plants.  There are no diatoms when my tank is green.  I suspect that planting your tank may reduce the diatom population.  Some here have albino plecos, who may (I don't have one) eat diatoms.  I have apple snails that do eat diatoms, but not at the rate that one could really say they act as a 'clean up' crew.   

Link to comment
Share on other sites

  • Regular Member

Diatoms are brown algae, they're the same thing. All new tanks get brown algae, but it usually goes away after awhile. Wiping down glass and removing any algae you see is a good start. As for the plants simply follow the same protocol; alternatively, a few members periodically bleach their plants. Keep them clean, wipe down slower growing leaves regularly and remove any seriously affected ones. The periodic pruning will do them good, it will encourage new plant growth. Apart from being unsightly, there's nothing harmful about them. They actually provide the Earth with a good deal of oxygen—when I set up my first high tech planted tank I had a diatom outbreak and they pearled like mad. I found it quite amusing. :rofl

 

16441122035_f3c317dff2.jpg

Edited by dan in aus
Link to comment
Share on other sites

  • Regular Member

If you want a planted tank, you might not want to try my method, but if you'd like to try an algae carpet then read further.

 

I personally just let the tank (apart from the front glass) be taken over by diatoms. Eventually the green algae should start appearing. The green algae then overtake the diatoms quite quickly, resulting in a beautiful green carpet for the goldfish to graze on and the keeper to enjoy, and no more brown stuff.

Link to comment
Share on other sites

  • Regular Member

Interestingly, I have always had diatoms in my tanks too. However, the heavily planted 180 gets next to none. Had a tiny outbreak (on some plant leaves and that was all) but after raising the lights a little I haven't seen any at all. The difference between the 180 and all of my other tanks is the number of plants and the number of fast growing plants. Just an observation :idont

Link to comment
Share on other sites

  • Regular Member

Do we have proof that high silicate water in itself equals more diatoms?

 

 - quick read-a-round.  Most of the easily accessible literature on silica/diatoms seems to come from the saltwater aquarium world where they add silica to the tank.

 

 - according to these sources, Troy's level is just into the 'high' category 

 

- all the additive solutions either don't work, or throw other problems into your tank while working

 

- heavily planted tanks, tanks with green water have fewer diatom 'problems' than tanks without

 

- 'wipe them off' seems to be the most effective and least invasive solution

Edited by motherredcap
Link to comment
Share on other sites

  • Regular Member

I just wipe it down and drain the tank to the sand. It's a never ending battle if you have silicates in the water, but it's only an aesthetic issue. One of my fish enjoys munching on the diatoms that appear on plants, but it grows faster than the fish can eat them. :rofl

I admit defeat to my more persistent enemy.

Link to comment
Share on other sites

  • Regular Member

Search plants and silicon.  You will find that terrestrial plants take up and use silicon.  So make a veggie filter for your tank.  This is basically a DIY pond-type upflow biofilter that uses hydroponic/aquaponic growth medium as it's medium and has plants growing in the top.  If you provide them with a good grow light, you can grow veggies or herbs in the veggie filter (and have an aquaponics system).  If not, use houseplants.  The veggie filter can also help with nitrate reduction.

 

Here are some DIY pond filter threads you can read.  When you come up with your own plan, run it past me.  I have done almost everything one can do wrong in making filters, so I'm pretty good at finding bugs.

 

http://www.kokosgoldfish.invisionzone.com/forum/index.php?/topic/100490-pond-filter-system-for-the-40b/

 

http://www.kokosgoldfish.invisionzone.com/forum/index.php?/topic/98620-upgrading-the-instant-pond/

 

http://www.kokosgoldfish.invisionzone.com/forum/index.php?/topic/110972-pond-filtration/  

 

http://www.kokosgoldfish.invisionzone.com/forum/index.php?/topic/100931-mini-bog-filter-for-aquarium-or-container-pond/  

 

Diatoms grow well in low light, while many other algae do not.  Increasing light intensity increases the competition with those others, particularly the much more attractive green algae.  Some have observed a decrease in the diatom population when they shortened the photo period.  So you might try increased light intensity over a shorter period of time.

 

The people who are into "algae scrubbers" claim these DIY filters can reduce diatoms, presumably by competition from the algae that grow rapidly in intense light.  You might have fun making one of these.

 

In response to a couple of comments/questions above, diatoms are brown algae if that means "algae that look brown."   However the biological term "brown algae" refers to multicellular marine algae like kelp.  Diatoms are sometimes classified among the golden-brown algae (which is a heterogeneous group even without diatoms) and sometimes given a group by itself.

 

Yes, silicon is a growth-limiting factor for diatoms.  The only time I have seen visible growth of diatoms on a pond liner was when I built a gravel bog filter for a deeply shaded pond.  A few days after I started running the filter, I came out to a pond in which the entire liner looked rusty with a humongous diatom bloom.  A few weeks later, the "rust" disappeared.  I can only guess that the combination of predation and the bog plants removing silicon from the water led to the population decrease.

 

Have you made the acquaintance of 

 yet?  I think you'll enjoy him.
 

 

 

Link to comment
Share on other sites

  • Regular Member

LOL, Lisa.  You know well that advanced training in science makes one careful about using the right terms and uncomfortable with the wrong ones.  

 

When I first started reading fish forums, the regrettable fish keepers'  jargon of "cycling" for "establishing nitrification" drove me crazy.  I couldn't even say it.  (I say regrettable, because those who aren't familiar with this jargon know what cycling means -- going round and round.  So when they are told at the pet store that they need to cycle the tank, they go home, set up the tank and filter, and let the water go round and round for a few days or even weeks, add the fish, and then wonder why they died.)  I can use the term now, but when someone refers to nitrification as the nitrogen cycle, it still drives me   :crazy:

 

"Brown algae" is an excellent descriptive term for diatoms, and I am comfortable with it.  However when someone says "Diatoms are brown algae," that's taking it too far for me and I just lose it.  (Sorry, Dan.  You didn't really say anything wrong.  It's just me.)

Link to comment
Share on other sites

  • Regular Member

Lol. I love it shakaho... only because I see myself in it. I'm an electircal engineer, and drive my wife crazy with 'technically precise language' that is not helpful to her.

Still, it seems the overall feeling is: diatoms aren't really bad for the fish, and the right plants can outcompete the diatoms for nutrients. As I'm planning on planting my tank, it seems picking the right plants will be the most beneficial path for the aquarium. (Well, that and wiping away the diatoms every water change.)

I have seen a few of the DIY aquarium guy's videos -- and the one you linked in particular. After seeing it, I thought: "You know, the water line for my kitchen sink runs right under the aquarium, so it'd be relatively easy to put in a tap for the aquarium..."

My wife vetoed the idea. <sigh...>

Link to comment
Share on other sites

  • Regular Member

I doubt any aquatic plant will outcompete diatoms, but look for stiff substantial plants.  They are also less tasty to goldfish.   If you get some semi-aquatic plants that grow up out of the water, you might have some luck.  Silicate is used to stiffen stems, so reed-like plants really suck it up.

 

Why did your wife veto automatic water change?  Maybe you need to spill a little more water when you do changes, then observe how a tap dripping into your tank would be spillproof.

Link to comment
Share on other sites

  • Regular Member

I've had my tank for just over a year. The diatoms in my tank were impossible to keep up with. I don't know the silicate content of my tap water.

 

I have tried more light, less light, fertilizers, Seachem Excel, more aquatic plants, wiping down every water change, floating plants, terrestrial plants, etc.

 

Finally I got a female bristlenose pleco. Her name is Princess. When Princess was in QT (for a month doing a 4 round treatment of prazi and 0.1-0.2% of salt), I would periodically put in brown algae covered plants from my goldfish tank into her tank. She would clean them up by the morning--they were squeaky clean. I basically trained her to clean algae off the plants because I have heard that some BN plecos will not touch plants.

 

Princess is now in the main tank and no more brown algae. I don't need to wipe anything down now. I use to have to bleach my anubias every 4-6 weeks. I don't need to do that now with Princess. She takes care of my diatom problem. I love her!!

Link to comment
Share on other sites

  • Regular Member

One of my largest fighters against diatoms are my lucky bamboo stems. I took out about half to let them grow out elsewhere and the diatoms took over instantly. I'll be putting the bamboo back in tonight.

I have about 45 or so stems in my tank.

My tank is a disfunctionally-ever-multiplying variety of Anubias species (Coffeefolia, Lanceolata, Nana, Barteri, Stardust, Angustifolia, Afzelii, Congensis, Minima, Caladifolia, Rotundipholia, Pectinatus, Pyinaertii etc..)and one large tentacle plant-- I mean Crinum Calamistratum which makes it easy to clean off and then drain the tank, also not appealing to the fish and will not break if they eat things off of the leaves. As for the Crinum, I gave up and let the diatoms have at it until I decide I've had enough. Not worth my time getting into those tiny crinkles and I worry I will rip it in the process.

Whatever doesn't just shake off can stay if it wants to so badly.

Edited for corrections because I just got out of geology class and am braindead

Edited by Chai
Link to comment
Share on other sites

  • Regular Member

LOL, Lisa.  You know well that advanced training in science makes one careful about using the right terms and uncomfortable with the wrong ones.  

 

When I first started reading fish forums, the regrettable fish keepers'  jargon of "cycling" for "establishing nitrification" drove me crazy.  I couldn't even say it.  (I say regrettable, because those who aren't familiar with this jargon know what cycling means -- going round and round.  So when they are told at the pet store that they need to cycle the tank, they go home, set up the tank and filter, and let the water go round and round for a few days or even weeks, add the fish, and then wonder why they died.)  I can use the term now, but when someone refers to nitrification as the nitrogen cycle, it still drives me   :crazy:

 

"Brown algae" is an excellent descriptive term for diatoms, and I am comfortable with it.  However when someone says "Diatoms are brown algae," that's taking it too far for me and I just lose it.  (Sorry, Dan.  You didn't really say anything wrong.  It's just me.)

 

It's okay, Sharon, I don't care. I do similar things when people talk about aesthetics. :rofl 

 

It was only a clarification that brown algae and diatoms are interchangeable terms around here.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...