Aquatic Plant Forum banner

Organics Analysis

108561 Views 450 Replies 29 Participants Last post by  Yorkie
The purpose of this thread is to (1) try to gather samples and data on the amount of organic pollution (i.e. Demand) that people have in their aquarium and (2) see if there is a correlation between the amount of organics measured (as TOC) and algae growth, specifically BBA.

The topic of 'organics' in the aquarium as a pollutant has always been very vague ... Often times, people talk about 'organics' as a problem in the aquarium but if you ask them about specific values of organics that cause problems or are acceptable or ask for specific articles about organic pollution level studies, most people are not able to provide any values or specifics. Instead they just wave their hands in the air and mumble generalizations like 'organics are bad and need to be as low as possible'.... how low is good? how high is bad? What are the average concentration values? Is there actually a correlation at all? That is the goal of this thread - to try to put generate analytical data on organic pollution (as TOC) and see if there is indeed a correlation between TOC concentrations and algae.

According to the Standard Methods Handbook, there are many ways to measure 'aggregated organic constituents' or 'organic pollution'. COD (Chemical Oxygen Demand) is the most common method of measurement and is defined as the amount of a specified oxidant that reacts with the sample under controlled conditions. Other methods of organic pollution analysis include BOD (Biologcial oxygen demand), TOC (total organic carbon) and TOD (total oxygen demand).

I would like to gather and analyse samples for organic analysis for their TOC content in order to see if there is indeed a correlation between the TOC of a particular aquarium and the presence of algae, specifically BBA. I work for an environmental laboratory, one of the instruments we have is a TOC analyzer (total organic carbon). This is a machine that measures the carbon containing compounds in your water by converting the carbon to CO2 and measuring the CO2 via an IR detector. Basically, there are two steps. In the first step, the sample is acidified. This converts all the inorganic carbon (HCO3- and CO3--) to CO2 and the amount of CO2 is determined. This portion is the TIC (total inorganic carbon). In the second step, an oxidant is added to the sample to decompose all of the organic carbon to CO2 and, again, the CO2 is detected. This portion is the TOC (total organic carbon).

If you are interested in participating and sending me samples for analysis, I ask that you collect and label your samples with the following information:

Name, Date of Collection, Aquarium Name (if you have multiple aquariums, usually the size), BBA present or not, CO2 injection or not, Water change frequency (and when your sample was collected with regards to them)

Also, be sure to include a sample of your source water (tap, RO water, RO water reconstituted).

For convenience sake, please collect samples in a DOUBLE SEALED ziplock sandwich sized bag, ~1/4 to ~1/2 full. Remove as much air as possible from the bags and seal the opening with packaging tape (or any other heavy duty tape like duct (or duck) tape, not scotch tape). Place all of the water samples into a larger gallon size ziplock bag for extra protection in case the bags leak. If you need or want to collect multiple samples over time, please refrigerate all samples for storage in order to minimize the amount of TOC degredation. Please PM me for shipping information.

I will analyze the samples and organize the results into a table format so we can then all analyze the data. If you would like your data to be presented as anonymous, please just include a note with your samples and i will report them on this forum as anonymous (but i need to know the actual name in order make sure i receive your samples and for proper sample tracking.)

Disclaimer. This analysis is for personal use only and all results may not be used for compliance testing and monitoring or legal use. I will not be held responsible for sample shipping, sample contamination and any loses that may occur.
See less See more
1 - 20 of 451 Posts
Can't wait to find out. I've got a tank with a BBA issue. And another one with hair/clado. Will send you samples soon.

This time with tracking...
It would be interesting to see the differences between tanks and what type of algae. Perhaps you can post a close up photo of the algae as well then we can match up the water test records to each photo and really build a substantial database.
I think APC is the one and only "guru" out there. This website really is on the cutting edge of the hobby. Other people do not share their research or findings, even Amano does not share any info he has learned by research. He shares his products for a price, but not the raw useful information. Which makes me wonder if he hasn't just happened on a formula that works but has no idea why it works.

I think this topic is fine in the algae section because we really want to get to the bottom of why algae grows.

Amanda has a few interesting tanks. They are all 2.5 gallon tanks on a shelf under the same light, but in each tank there is a different species of algae that dominates. I believe she even has the same substrate in each tank. I wonder what the differences are between each of her tanks. That would be really interesting.
See less See more
Well said Phil.

Not convinced his group actually has all the answers. Without peer review and additional experiments by people outside of his group it is hard to believe his results are 100% accurate. .
Big update ... Just in time to relax and get ready for Aquafest 2013! Here are analysis results for samples from Cavan Allen (CA), Tim Gross (TG), Zapins (MT). For clarity sake, results below my reporting limit of 0.01 ppm in the micro nutrients table will be reported as "<" (less than the detection limit). B results are not available (n/a).

| Sample               | Al  | B   | Ba  | Co  | Cu  | Fe  | Mn  | Mo  | Ni  | Sr  | V   | Zn  | 

| CA Tank 10/2/13      | 0.06| n/a | 0.03|  <  |  <  | 0.03|  <  | 0.01|  <  | 0.14|  <  | 0.03|
| MT Old Home Tap 10/8 |  <  | n/a |  <  |  <  | 0.01|  <  |  <  |  <  |  <  | 0.10|  <  |  <  |
| MT Home Tap 10/8/13  |  <  | n/a | 0.07|  <  | 0.01|  <  |  <  |  <  |  <  | 0.06|  <  |  <  |
| MT Apt Tap 10/8/13   |  <  | n/a |  <  |  <  | 0.06|  <  |  <  |  <  |  <  | 0.24|  <  | 0.10|
| MT 90g Apt Aq 10/7/13|  <  | n/a | 0.04|  <  | 0.04| 0.14|  <  |  <  |  <  | 0.27|  <  | 0.18|
| MT 90g Home Aq 10/7  |  <  | n/a | 0.05|  <  | 0.26| 0.01| 0.01|  <  |  <  | 0.06| 0.01| 0.03|
| TG Tap 10/12/13      | 0.02| n/a | 0.04|  <  | 0.01|  <  |  <  |  <  |  <  | 0.27|  <  | 0.19|
| TG 20g Aq 10/12/13   |  <  | n/a | 0.02|  <  |  <  |  <  |  <  | 0.01|  <  | 0.26|  <  | 0.02|
| TG 40g Aq 10/12/13   |  <  | n/a | 0.02|  <  |  <  | 0.03|  <  | 0.01|  <  | 0.25|  <  |  <  |

| Sample               | K   | Ca  | Mg  | Na  | TIC | TOC |Gen. Hard. (dGH) | CO3 Hard. (dKH)| 

| CA Tank 10/2/13      | 33.0| 26.4|  7.1| 19.6| 11.2| 10.6|  95.0 ( 5.3 dGH)| 93.3 ( 5.2 dKH)|
| MT Old Home Tap 10/8 |  1.9| 39.1|  9.2| 28.5| 20.1|  1.5|   136 ( 7.6 dGH)|  168 ( 9.4 dkH)|
| MT Home Tap 10/8/13  | <1.0| 20.2|  7.8|  6.7| 14.9|  1.3|  82.3 ( 4.6 dGH)|  125 ( 7.0 dKH)|
| MT Apt Tap 10/8/13   |  6.7| 58.8| 19.3| 48.0| 22.6|  2.5|   226 (12.7 dGH)|  188 (10.6 dKH)|
| MT 90g Apt Aq 10/7/13| <1.0| 20.0|  7.4|  8.3| 16.5|  4.2|  80.5 ( 4.5 dGH)|  131 ( 7.3 dKH)|
| MT 90g Home Aq 10/7  | 23.2| 54.1| 19.3| 55.4| 15.7|  5.6|   215 (12.0 dGH)|  138 ( 7.7 dKH)|
| TG Tap 10/12/13      |  3.3| 41.3| 11.3| 49.3| 12.7|  1.7|   150 ( 8.4 dGH)|  106 ( 5.9 dKH)|
| TG 20g Aq 10/12/13   | 57.1| 35.3| 10.3| 46.5|  8.9|  1.6|   133 ( 7.5 dGH)| 74.3 ( 4.2 dKH)|
| TG 40g Aq 10/12/13   | 70.1| 39.1| 10.9| 49.3| 11.5|  3.3|   143 ( 8.0 dGH)| 96.2 ( 5.4 dKH)|
All results are in units of mg/L (ppm). Metal analysis results were analyzed by ICP-OES. TIC & TOC analysis results were analyzed by method SM 3510 C - Heated-Persulfate Oxidation. General Hardness & Carbonate Hardness are in units of ppm CaCO3 eq (calculated). Carbonate Hardness (KH) were calculated from TIC, not a titration (so they may not be equivalent... i still have to test them to see). Please note - Limited QA/QC solutions were run on these samples and these analysis results are for personal use only. These results may not be used for regulatory reporting purposes or compliance testing. If anyone else would like their water tested, please feel free to contact me. Thank you.
I wonder if this algae has to do with the TOC level or if it has more to do with the toxic levels of copper in my tank water. I'd guess the copper, but we'll let the data pile up.

My 90g home tank when I took the water sample:

Same tank before:

See less See more
I'm dying to know what the results were for my 180g (please post the full details in Cavan's thread as well!). That tank uses straight uncut RO water only with no re-mineralization. I have it connected to my automatic water change system so it gets daily new RO water. It also has a stupid amount of organics in it. There are literally pounds of moss (decaying moss as well) all over the bottom and then cabomba growing over the top shading out everything, so there is very little algae (except some BBA near the top). I honestly don't understand why I haven't seen deficiencies in that tank yet since I never add micros or macros or even Ca/Mg.

As for the copper in my tank. I'm not sure. It certainly has quite a lot of debris all over the place and organics from all the flake food and 200+ endlers.

Is 5.6 TOC a "high" level? I think we need a lot more results. Look at Cavan's results, he has double my TOC and I don't think he has huge amounts of algae.
See less See more
His other thread:

He had a zinc toxicity which was stunting his plants. I don't think he really has algae issues as far as I remember.

If you can find info on TOC I'd like to see it, I haven't found much background info on it.
Be sure to send a sample of your tap water as well as the tank water.
An interesting speculative article on the topic of TOC (basically) and algae.

What do you make of it?

I'm still having trouble finding the support for claims 1-3 in the literature.
Why not make your own standards? A known amount of fertilizer (weighed on a scale) in distilled water.
I wonder if it isn't more to do with allelopathy than sugars.

We all know that when plants are happy algae isn't. Which makes me wonder if plants aren't suppressing the alga's growth in some way. This is also consistent with observations that algae isn't triggered to bloom in high nitrate and phosphate environments. The funny thing is, in the wild it has been well documented that nitrates and phosphates do cause algal blooms, but not in our tanks. We tend to keep a much higher plant density than in the wild and so perhaps these algaecidal chemicals build up to higher than normal concentrations and stop the growth of algae, which matches the whole high NO3/PO4 doesn't cause algae observations.

Alternatively, algae could just be programmed to bloom when certain nutrient criteria are met. The most obvious example is for green water. Add some ammonia and vuala. Perhaps each algae has a certain ratio or nutrient it waits for to change in a favorable direction before it blooms and it just so happens that the values and ratios we keep our tanks at tend not to favor any of those bloom criteria.

Then there is the whole sugar post which I linked to.

There really seem to be an almost limitless number of possibilities for the cause of algae. I don't know how we can figure out what is more important without some very high level chemistry experiments.
See less See more
Making standards is one thing. Verifying that your calibration curve is correct involves analyzing a certified reference material against your calibration curve and checking that it analyzes correctly. Also, in order to make standards, you need all of the materials listed above to ensure that your results are as accurate as possible.
True but using a hobby test kit isn't really that accurate to begin with. With no digital read out you lose a good bit of accuracy simply because it is based on the human eye and matching colors on a card. I think at best its an approximation even with standards made up.

I wonder if you can make a standard up, then seal it and keep it for reference? Or will it degrade and change color over time? I seem to remember having a nitrate test kit in botany class that had small vials with different strength solutions in it that you compared the color to rather than a print out card.
It is too bad we don't all read Czech then we wouldn't have to reinvent the wheel :/
Is there a translation to English for the czech site you linked? I think a lot of us would be interested in reading what has been written about.
I think you are right taking out those elements from the result table. I don't think they have much to do with plant and algae issues.

I think I remember you saying your machine wasn't set up for nitrogen or phosphates, but would it be possible to add sulfur to the list of things to test?

Also as a side note, my apartment tank has had green spot algae for quite some time now which is on both leaves and the glass. I know conventional wisdom says GSA is cured by low PO4, however, I keep testing my PO4 levels and they are 1 ppm out the tap and then I add another 1.5 ppm for a total of about 2.5 ppm. I was reading through some old posts and I found two other possible causes. The first was Tom Barr chanting his CO2 mantra - but my CO2 is at 5 bbps and I don't want to go higher for fear my rainbows will die (already lost 2 to high CO2 levels during acclimation). The other was a post by freemann from 2008 that mentioned potassium was needed in order to help PO4 absorption.

I looked over at my test values for my tank and found that my K levels are very low. So I wonder if there is some truth to this. According to some other unrelated research it seems that potassium levels should ideally be around 2x higher than calcium levels (roughly equal with nitrate levels). So I think I will try adding some more potassium and see if that helps reduce GSA growth. Maybe around 15 - 20 ppm K.

| Sample               | K   | Ca  | Mg  | Na  | TIC | TOC |Gen. Hard. (dGH) | CO3 Hard. (dKH)| 
| MT Apt Tap 10/8/13   |  6.7| 58.8| 19.3| 48.0| 22.6|  2.5|   226 (12.7 dGH)|  188 (10.6 dKH)|
| MT 90g Apt Aq 10/7/13| <1.0| 20.0|  7.4|  8.3| 16.5|  4.2|  80.5 ( 4.5 dGH)|  131 ( 7.3 dKH)|
See less See more
I want to say that this is top 5 most interesting threads I've ever read.

Jeffy, I would never expect you to re-test all the samples! That would be horrible! I was asking to see if it was possible and relatively easy for you to add the S to any future tests. I think even if only sulfate were tested it might still be useful since most people tend to add sulfates (MgSO4, K2SO4, etc...). If it is difficult then no worries, I'd rather have it be easy for you to test and keep getting these amazing results than get an S value and make it difficult on your end.

I think it is only fair to make it a requirement that if you get your water analyzed by Jeffy you must also record what algae/how much, if you are using CO2, Excel and any other conditions so we can properly analyze the results. Pictures would also be beneficial.

As for the results, a lot of really interesting things in there. I personally like the K column next to the Ca and Mg since those three affect each other, I could move it if you don't object? And I can fill in any changes we need to make to the charts, just send me a PM or write it out in this thread. Also would you like me to move the TOC value so it sits directly next to the BBA column? Might make referring to values easier?

It seems that there is no correlation between CO2 and BBA at all. Of course, we can't know exactly what concentration everyone has but to me if there was such a strong relationship between CO2 and no BBA I think we'd see more of that in the data. It looks more like BBA and CO2 are unrelated.

On the other hand it seems the TOC and BBA values are much more related. It looks like any tank over 5 has BBA and any tank below 4 does not. I think it is too early to tell for sure (and I'll have to run this through Prism 5 for the statistics on it). Also, I see that "BM's Tank 10/17/13" has a very high TOC of 10.4 but he has no BBA. He does happen to have an extremely high iron level of 2.7 ppm. Perhaps they are related? The only other person with high values is Aaron, but we need to fill in his BBA status to see if there is anything to the high iron and BBA theory.

Also, BriDroid I don't think potassium is causing algae, you actually have a pretty good ratio of K:Ca:Mg, there should be more K than Ca to avoid any kind of competition between the uptake of those nutrients according to research in hydroponics.
See less See more
Diatoms are not algae (they don't photosynthesize) so they should not be taking up plant nutrients at all. They are dinoflaggelates and are said to be related to high silicates in the water, or high organics which they supposedly feed on. This is why they tend to disappear in new tanks as they mature (silicates are depleted and organics stabilize).

Speaking of silicates, is that something that could be added to future tests without too much trouble? It would be nice to know if that silicates = diatoms statement is true since it has been said around the hobby for decades.
Good catch, I meant to say the *dinoflagellates* we know as "brown algae" are not photosynthetic.
Not all species photosynthesize and the brown one that is easily scraped off objects in our tanks does not. It is well documented. It can grow in total darkness.

University of California said:
They may be photosynthetic or non-photosynthetic; about half the species fall into each category. The photosynthetic dinoflagellates are second only to diatoms as primary producers in coastal waters.

Non-photosynthetic species of dinoflagellates feed on diatoms or other protists (including other dinoflagellates); the genus Noctiluca is large enough to eat fish eggs, and is able to swallow protists larger than itself. Some species will parasitize other organisms, such as zooplankton and other protists, filamentous algae, or fish.
It is surprising you have such a high TOC from the tap. I wonder what the limit is on TOC for drinking water. I feel like someone has mentioned it before in another post or thread but I cannot remember where. Might have been Yo-han?
1 - 20 of 451 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.