The diatoms are back

[gingerinaustin]

The diatoms in my 55 gallon had finally disappeared before I converted the tank to live plants a month ago. Now they are back with a vengeance. Why?? Aren't the plants supposed to be eating the nitrates?

I started dosing the tank with KNO3 and KCl last week; 1/4 teaspoon every other day to bring the nitrates to 5 ppm and the KCl to probably around 10 ppm per Chuck Gadd's calculator. API test kit indicates 5 ppm nitrates (some leftover test strips indicate the nitrates are much higher but the API test is more accurate--right??) I'm still dosing Excel every day. I dosed iron once with the last water change. I haven't started dosing phosphates as the tank water has .5 ppm. I haven't started traces.

Another problem is that my amazon sword is getting that lacy-leaf look. I'm sure that's some deficiency but of what? I put a Seachem Flourish root tab in the Eco-Complete underneath the sword two weeks ago, also one under the sag, they both still look crummy.

Any suggestions?

:angryfire: I hate diatoms. :angryfire:

[Ajordan]

I would continue to lay off the phosphates as diatoms seem to love them... Are you over feeding? Are you suuuuure you aren't over feeding?

Also, what sort of lighting do you have? How old are the bulbs?

[ct-death]

New tank? Glass or Acrylic?

Basically Diatoms are persitant for about the 1st year in new tanks.

Harmless and easy to remove manually, but unsightly. Otos work great on this, as will your Platies/Mollies (the snails will get to them also).

Alos, increasing the light will tend to help as well, but this can eaisly casue other issues such as algae.

How did you rid yourself of it in the past (it never really goes away BTW)?

Here's a Great Starter page for info: http://www.plantgeek.net/article_viewer.php?id=9

[Nolapete]

http://www.theplantedtank.co.uk/algae.htm is a great algae diagnosis and treatment guide.

Phosphates do not cause diatom bloom. Insufficient light and excess silicates do.

Check rexgrigg.com for dosing ferts information. Phosphate dosing is a must. I noticed significant growth in my plants when I started dosing it.

[Star_Rider]

:iagree: silicates seem to be one of the most important factors.
if the tank is glass and relatively new this problem tends to be more common.

as the tank mautures and you start dropping silicates then there may be less diatoms.

silicates can also come from the water source and or substrate.

[mudskippers]

-just a side question, because I'm trying to learn all of this plant talk.. lol


What is KCL?? Potassium Chloride???????
What does this do for plants?? Just wondering, like I said, I'm trying to educate myself because soon I will be dosing my tank... Trying to fill my head with knowledge first. ;)

[ct-death]

1st Q Yes, you are correct
2nd Q, Potassium is found in leaves prodominatly (and a root too I think), and a good indicator of a potassium depleated plant is one that looses it's leaves or develops whole in mature leaves. This compounds aids in enzyme exchange and leaf functions. Again, in aquatic plants I think it also plays a factor in roots as well.

Hope that helps!

Also, I would simply do a Google on Planted Aquariums or Tanks. There is a lot of good info! I'll link 2 of my favorites in a minute

Here: http://www.plantgeek.net/ and http://rexgrigg.com/

ENJOY! ;)

[mudskippers]

1st Q Yes, you are correct
2nd Q, Potassium is found in leaves prodominatly (and a root too I think), and a good indicator of a potassium depleated plant is one that looses it's leaves or develops whole in mature leaves. This compounds aids in enzyme exchange and leaf functions. Again, in aquatic plants I think it also plays a factor in roots as well.

Hope that helps!

Also, I would simply do a Google on Planted Aquariums or Tanks. There is a lot of good info! I'll link 2 of my favorites in a minute

Here: http://www.plantgeek.net/ and http://rexgrigg.com/

ENJOY! ;)
Thanks :)

[fgump]

I have a bad problem with brown diatoms in my tank also. It is a new tank, about 5 months old. The diatoms weren't to bad, and I could go two or three weeks before cleaning them. Since I've added a better a light, plants, DIY CO2, and ferts, the population has exploded. I have to clean them every 5 days or so now. I went from about .7 watts/gallon to 2.5 watts/gallon with the new light.

I think it's either the plastic rock I had in my tank, or the 'gravel'. I got the gravel at PetsMart and I don't think it's real gravel, though it looks like it. I'll have to go back and see what it's made of. I've removed the plastic rock recently. Although it was made for aquariums, I'll see if that helps any. If that doesn't, I might be replacing the substrate :(

[mudskippers]

Diatoms go away on their own right?? I know that in many setups they can appear on the decor and the glass. So far, my tank has been up for about 3 months or so, and I have diatoms on my glass. I wiped most of them away execpt on my back glass, becuase it was hard to get to.... I can just leave them be and they will go away on their own right??? They dont bother me...

No harm in leaving them right?

[phanmc]

Diatoms can crop up in older tanks. I recently rescaped one of my tanks and removed a large amount of plants, and sure enough I got brown algae. Their growth stopped when the plants began to fill in.

To the OP, how much light are you using? I suspect it might be CO2 related.

[gingerinaustin]

Sorry--very busy at work today, only now having time to respond. The tank's been up and running since April 7, so it's 6 months old; fully cycled (0 ammonia, 0 nitrite, 10 ppm nitrate) since June 11. It's a glass tank. The diatoms appeared about a month into the initial cycle (mid-May) and were completely wiped out around end of July by what Red and I now fondly refer to as Rent-A-Pleco (Red really really wanted it so I relented but after I realized he'd gotten a sailfin, I insisted we take it back a week later).

I converted the tank from white Estes gravel & plastic plants to Eco-Complete & live plants on September 2 at which time I upgraded the lights from .55 WPG to 1.75 wpg, so the T-5s are about a month old. I retained all the filter media and there was no appreciable mini-cycle that I could discern after The Big Switch--ammonia and nitrite remained at zero. The diatoms reappeared end of September and are now everywhere again, as they were prior to Rent-A-Pleco. The platies and gouramis do love to peck at the diatoms but they can't do the scouring job Rent-A-Pleco did. I feed them in the morning and I don't feed them more than they can eat in 30-45 seconds. Red swears he only gives them an itty-bitty pinch in the afternoon (if he can't give them their "snack" it will make Red very sad). I do dose Excel daily but have no pressurized CO2.

I know the diatoms aren't harmful per se but I can't stand they way they look and my pennywort and bacopa is pretty well inundated with the stuff to the point that I wonder if the diatoms are letting enough light through for optimal growth!

[phanmc]

Lighting isn't too high unless those T5s are high output.

I'd start dosing traces and bring the phosphate to 1, no point in limiting the plant growth and they don't cause algae if overdosed.

[gingerinaustin]

They are indeed HO T-5s. I have two of the 24" freshwater version of these lights over the 55 gallon:
http://www.drsfostersmith.com/Product/Prod_Display.cfm?pcatid=16770&Ntt=t%2D5&Ntk=All&Ntx=mode+matchallpartial&Np=1&N=2004&Nty=1
I was warned they might be too high output for a non-CO2 tank. But, I thought diatoms preferred lower light, not being a true algae--is that not correct? (I've read conflicting things about diatoms and light so I'm not certain). I do have a little green algae, but that doesn't bug me--I kinda like its mossy look--bit I can't stand the dirty rusty diatoms. At least it's not as visible on the Eco-Complete as it was on the white gravel.

Our tap water has a silica content of 8.2 ppm. I don't know if that's high or low. I do think a big part of the problem is that except for the hornwort, none of the plants are really thriving. If the plant growth would take off, there would be fewer nutrients left for the diatoms. There is some new growth here and there, but nothing spectacular. It's hard for me to believe I have too much light in that regard--I expected the H. callitrichoides might not make it but even the ambulia (L. indica) and green temple plant (H. corymbosa) died.

Mr. and Mrs. Apple Snail were not responding well to one of the fertilizers, so I moved them to the 5 gallon and ramped up the Excel, NO3 and KCl dosing in the 55 gallon. I guess I'll start traces, bring up the phosphate ever so slightly and see if I can't get the plants growing mo' bettah.

[phanmc]

Diatoms photosynthesize so they do like light, but they are able to tolerate lower light levels.

HC actually doesn't require high light, though it's a slow grower so it will look like it's not growing in lower light. It needs good CO2 though, haven't been successful growing HC without CO2.

Anyways, the problem isn't too much lighting alone, it's not enough CO2 and nutrients to go along with the higher light. Higher light drives faster growth, which requires more nutrients. Once a nutrient becomes deficient growth becomes erratic and stalls. Same thing can happen in a low light setup, don't do a water change for a couple of weeks and hello algae (unless you dose ferts).

So introduce the full range of nutrients to make sure nothing is deficient. Excel everyday can't be cheap, might be time to save up for a CO2 system.