# diatoms still in tank after a year



## max chavez (Aug 7, 2009)

I don't think that excel will help diatoms. Otocinclus will take care of a portion of them. But, it is odd that they are persisting for so long. Maybe a pic would help to get some opinions on whether they are actually diatoms or something else?
good luck


----------



## msawdey (Apr 6, 2009)

enlender said:


> hello all ive had my tank setup for over a year and Ive been dosing excel like is recommended but its not helping the diatoms. i stopped dosing for a month and still diatoms persist. any ideas? im not running any co2 and have 1wpg


 
Hi enlender,

Chances are that you may never get rid of them. Ive had my tank set up for 2 years, with co2, and proper doing and still get them mildly. I think that it is a sign that your tank is healthy and as long as the fish and plants look good and are growing i dont think you have much to worry about. 

but if it does get bad or is, post some pics to give an idea of what we are dealing with.


----------



## enlender (Mar 23, 2010)

well i just got 2 more ottos and a nerite snail to see if that helps.. my guess is that i need more plants to soak up nutrients. but ill post a pic when they return i cleaned my glass and water changed today so its sparkling!!


----------



## Lance Uppercut (Aug 22, 2009)

Check your phosphates, and test for silicates if you have the ability to do so. 
Have you tried running any phosphate absorbing media in your filter? I'm pretty sure most aluminum based resin (phos-zorb) as well as granular ferric oxide will take out phosphate as well as silicates.


----------



## captain_bu (Oct 20, 2007)

enlender said:


> hello all ive had my tank setup for over a year and Ive been dosing excel like is recommended but its not helping the diatoms. i stopped dosing for a month and still diatoms persist. any ideas? im not running any co2 and have 1wpg


Since you stopped dosing for a month and the diatoms did not go away that pretty well confirms they are not related to the levels of ferts in your tank. Skip the phosphate absorbing media, you need phosphates to grow plants, they do not cause algae.

Plants need nutrients to grow, hard to say how much you should be dosing since you do not indicate what type of lighting you have. 1 wpg of T5HO is a LOT more light than 1 wpg of T8. If the tank is truly low-light you can add low doses of ferts once a week. If you are using T5 or T5HO lighting you will need to add higher doses of ferts. Those will help keep your plants healthy and growing but the ferts will not get rid of the diatoms. If you are using T5HO you may need a carbon supplement too, for a small tank you could try DIY CO2 or Excel but once again that is only to keep your plants healthy and free of other types of algae. I haven't found Excel effective against diatoms.

Wish I had a better answer for you. I have one tank that also still has some diatoms despite being set up for almost a year and a half now. I run pressurized CO2 in that tank so I don't think that will help you get rid of them. I read lots of posts that claim high silicates cause diatom problems but have never seen a definitive answer as to whether this is true. 

At this point the diatoms in my tank only seem to settle on the lower sections of plants with fine leaves and they are no longer very bad either. What seemed to help get them under control was keeping the tank really clean. I was doing bi-weekly 50% water changes for a while and that helped a lot. Vacuuming the surface of the substrate lightly to remove mulm and organic debris helped a lot too. Make sure you keep your filter clean too.


----------



## OverStocked (May 26, 2007)

Lance Uppercut said:


> Check your phosphates, and test for silicates if you have the ability to do so.
> Have you tried running any phosphate absorbing media in your filter? I'm pretty sure most aluminum based resin (phos-zorb) as well as granular ferric oxide will take out phosphate as well as silicates.


Phosphates do not cause diatoms and there is no need to remove phosphates as plants do this. If you do it, they will suffer.


----------



## houseofcards (Mar 21, 2009)

max chavez said:


> I don't think that excel will help diatoms. Otocinclus will take care of a portion of them. But, it is odd that they are persisting for so long. Maybe a pic would help to get some opinions on whether they are actually diatoms or something else?
> good luck


I agree. Are you sure they are diatoms and not mulm? What fauna do you have?


----------



## macclellan (Dec 22, 2006)

we talking green or brown?


----------



## Lance Uppercut (Aug 22, 2009)

over_stocked said:


> Phosphates do not cause diatoms and there is no need to remove phosphates as plants do this. If you do it, they will suffer.


I was referencing the PO4 absorbers more for the silicate absorbing properties.... that being said, PO4 higher than 1ppm could cause undesirable effects... we could also overlooking a nutrient imbalance, for example, if the N or K were super low, the plants may not have been able to use the available phosphate, allowing it to be used by other things (most likely cyano or nuisance algae, not so much diatoms).

Another thing, are we sure we're talking diatoms? OP, you got a pic for us?


----------



## OverStocked (May 26, 2007)

> > Phosphates do not cause diatoms and there is no need to remove phosphates as plants do this. If you do it, they will suffer.
> 
> 
> 
> ...


Cite a current source indicating PO4 greater than 1ppm means anything. I dose to 3ppm and have never had an issue. Less and I PO4 does not cause algae at that level. If you doub me... ask Tom Barr or Hoppy or about a bajillion other folks. 

Sent from my Droid using Tapatalk


----------



## Lance Uppercut (Aug 22, 2009)

over_stocked said:


> Cite a current source indicating PO4 greater than 1ppm means anything. I dose to 3ppm and have never had an issue. Less and I PO4 does not cause algae at that level. If you doub me... ask Tom Barr or Hoppy or about a bajillion other folks.
> 
> Sent from my Droid using Tapatalk


I can site no source other than my own experience. 
Super short version:
-Nuisance algae/cyano was present.
-Phosphates were high (most likely higher than 3ppm).
-Phospates were lowered by chemical media.
-Problem ceased.
-Dosing/ maint. schedule remained the same for the duration.

...but I digress. We're talking about phosphates when we should be talking about diatoms. We're talkin bout diatoms here people. Diatoms! 
Diatoms?


----------



## Kathyy (Feb 22, 2010)

I have had the exact opposite experience. Nuisance algae, high phosphate in the tank. Resin in, no help at all. Removed the resin, added nitrate, algae went away. If one nutrient is high that means another nutrient is low. Planted tanks are nutrient rich, makes more sense to dose the low nutrient than try to balance the tank by limiting the ones that are too high.

My 10 gallon using Excel got a grain of nitrate, phosphorus and micros at water changes.


----------



## mistergreen (Dec 9, 2006)

how big is your tank and how many fish do you have? I have the same issues. I think my bio-load is a bit high and that could be the reason.


----------



## enlender (Mar 23, 2010)

ok so i was a bit vauge in my first post about my tank.

55g
t8 strip light the crappy all glass ones.. yea that..
all perimeters are normal
ph is 7.0
substrate is eco complete

3 juvie angels about silver dollar size
4 small kribs about an inch 
5 neon tetras .... well there neons i think we all know how big they are lol
2 silver hatchets same size as the angels
5 ottos (got 2 yesterday)
1 nerite snail (got yesterday) 

the diatoms im haveing in my tank are brown and generally low around the substrate line but then in random spots along the back and the front of the tank. rarely on the sides.

i have only added the snail and the 2 other ottos to see if they will be able to help it if not after about a week ill cut down the light time on the tank. right now its 10 hours ill bump it to 8 and see how it goes.


----------



## dutchy (Jul 31, 2009)

Cause of diatoms:

- Not enough light 
- Silicates (SiO2) 

Since light doesn't seem to be the problem here, Check the SiO2 level. Also Check SiO2 level of your tap water. Maybe you have stones in your tank or substrate that leaches SiO2.

Don't stop dosing.


----------



## sewingalot (Oct 12, 2008)

over_stocked said:


> Cite a current source indicating PO4 greater than 1ppm means anything.


Yes, I can cite several sources. There is evidence excessive PO4 can lead to Eutrophication in nature.

http://toxics.usgs.gov/definitions/eutrophication.html

http://www.water-research.net/Watershed/phosphates.htm

Can you site any scientific sources showing phosphates do not mean anything? Of course, these articles I gave are probably outdated, lol.


----------



## dutchy (Jul 31, 2009)

Excessive? Please clarify how much is "excessive"? CAN lead? When? How?

Do the studies include NO3 and CO2? Or is it only when there's a lot of PO4 in a further limited environment? Big difference.

If PO4 causes algae, everyone with high PO4 should have algae. If that is so, why don't I have any at 3 ppm of PO4?


----------



## Jeb (Dec 28, 2009)

Ive got the same issue as OP and still cant figure out how to fully get rid of it.


----------



## StaleyDaBear (Apr 15, 2010)

This problem is all about silicates. I have the same problem in my 55 gallon right now, which is stocked with 8 oto's 3 siamensis and some nerites. and they can't keep up. my tap water is high in silicates, and my substrate, Turface, also has SOME silicate in it. Unfortunately, theres no real way of removing the silicates naturally so I have purchased a UV/Diatom sterilizer/filter to tackle the problem. A choice for you OP?


----------



## shane3fan (Nov 2, 2009)

StaleyDaBear said:


> This problem is all about silicates. I have the same problem in my 55 gallon right now, which is stocked with 8 oto's 3 siamensis and some nerites. and they can't keep up. my tap water is high in silicates, and my substrate, Turface, also has SOME silicate in it. Unfortunately, theres no real way of removing the silicates naturally so I have purchased a UV/Diatom sterilizer/filter to tackle the problem. A choice for you OP?


 
How do you explain the fact that I have one tank out of 4 in my home that has diatoms all over the plants--and the rest dont? Same water, same substrate, same dosing, only one fish in the tank with diatoms-but two of the other tanks have no fish at all. Similar lighting in all tanks. 

I actually think I have a handle on the diatoms right now--I cleaned them all off and changed the lights out. Went from two 15w T8 lights on a 10 gal to 2 15w cfl bulbs. That was the only real difference I could find between two of my tanks--and one had diatoms, the other did not. We shall see if it stays away.?.


----------



## StaleyDaBear (Apr 15, 2010)

it is then a process of elimination as to where you silicates are coming from. what are you doing different to this tank, that your aren't with the other three? i guarantee its not a lighting issue as diatoms can survive in the lowest light environments. some plants have been known to take up more phosphate than others, and if this is the case, your silicatehosphate ratio might be a little too high. if you are not going to go with a sterilizer or phoszorb i would simply check your phosphate levels and add 1-2ppm/week until the diatoms starve. they will be back.


----------

