Nitrate 160 nitrrite 0.5 help
- Thread starter ccole
- Start date
Hi bex84,
I would be very careful taking anything from this thread as there is a lot of duff info here.
Chris.
I would be very careful taking anything from this thread as there is a lot of duff info here.
Chris.
Hi,
Water is a very complex subject and one which I can not fully do justice to as I'm not a qualified chemist. There are books dedicated to this alone and any quick search on the web will reveal a plethora of info. There are also lots of different opinions as to the best way forward, some are based on fact and some seem to be spouted out as sales speel.
It seems to me for starters that there is some confusion with some of the terminology. So I'll briefly run through what they are.
PH is the measure of acidity. Its a logarithmic scale which means that for every 1 unit of measure there is a 10 fold difference. There are many different types of acids which can be held in the water column and PH is a combined measure of them all, i.e. different acids are given off from wood, peat, CO2, buffers etc, etc. Some of the acids are beneficial and some not so.
GH is general hardness and is often also referred to as permanent hardness. It basically consists mostly of calcium and magnesium usually but not always in a ratio of around 3:1 respectively.
KH is Carbonate hardness and is often referred to as temporary hardness. It consists mostly of carbonates which can be used up by rotting matter and therefore tends to fluctuate over time hence its name. It has a buffering affect on the PH to keep it stable. This can be a bit of a double edged sword especially if you are trying to alter the PH with PH buffers.
Ammonia, nitrite and nitrate are by products of the three stages of the nitrogen cycle and should all be kept to a minimum as your already well aware.
TDS is a measure of Total Dissolved Solids which is usually measured with an electronic pen type meter which has a pretty much instant and fairly accurate readout displayed in PPM (parts per million). RO ( reverse osmosis) water has a TDS of 0ppm and is too pure alone to keep fish in. It therefore has to be remineralized before use.
If you wish to start altering water parameters adding more chemicals to change what is already some form of concoction coming out of the tap is not the way to go. The often high levels of buffers will necessitate large amounts of chemicals to counter them and all that does is raise the TDS which many fish are very sensitive to especially Amazonian species. What you therefore need is a blank canvas to start from which is why RO water is often used and then remineralized to suit. If your tap water isn't too bad you may sometimes get away with using a HMA filter instead which is cheaper and more efficient to run and removes all the heavy metal toxins from the water. RO water can be mixed with tap water but why put any possible pollutants that you've just paid to get rid of back in? So it doesn't make sense. It can also be mixed with HMA water (which any RO water filter can also produce just tap off pre-RO membrane filtration stage) which is the way many choose to go or it can be reconstituted to known levels with a mixture of different salts, which is my preferred method..
I mentioned previously how notoriously inaccurate Nitrate testing with home test kits is. A quick glance through any reef keeping forum will bear this out. Also worth having a quick look here:-
[ame="http://en.wikipedia.org/wiki/Nitrate_test"]Nitrate test - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Nuvola_apps_edu_science.svg" class="image"><img alt="Stub icon" src="http://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Nuvola_apps_edu_science.svg/35px-Nuvola_apps_edu_science.svg.png"@@AMEPARAM@@commons/thumb/5/59/Nuvola_apps_edu_science.svg/35px-Nuvola_apps_edu_science.svg.png[/ame]
At best home test kits need to be calibrated against a known reference solution EVERY time they are used and at worst are completely misleading. How can you react to readings that can't be trusted? You may end up changing things that don't need changing or worse miss something that is a threat to your fish thinking that the reading is good.
You have to remember that manufacturers have a vested interest in selling things to uninitiated aquarists (often sales lead to more sales) and far from everything that you read in their glossy brochures and subsequently spouted as gospel is actually true. Next they'll be telling you that Phosphates cause algae.........Mark my words.
The way to know that Nitrates aren't a problem for you is to be safe in the knowledge that your water changing regime is adequate and the the water that you use is ok. You can go online and get water reports from your local authority which will detail the nitrate levels in your area but I would expect them to be ok as most fish will toleate the nitrates themselves without problems within reason.
Its the actual process of producing the Nitrates within the tank that is the real issue here.
Plants consume nitrate (as well as other compounds) and removing plants doesn't remove nitrate. It will actually have quite the opposite effect as removing or decreasing the amount of planted matter will decrease the total amount of nitrates consumed. Plants also have many other needs and aren't by any means a simple solution. I would hazard a guess that you'll run into more problems than you already had if you don't supply the plants with everything they need and expect them to just grow willy nilly.
If plants are unhealthy they will decay and then will cause algae issues and produce large quantities of ammonia. So their health is also of paramount importance if this is the way you intend to go. Again maintaining a healthy planted tank is a huge issue which I can't do justice to in a few lines here but it does offer a very good solution. Just don't think its the easy way forward cause it ain't, far from it.
Chris.
Water is a very complex subject and one which I can not fully do justice to as I'm not a qualified chemist. There are books dedicated to this alone and any quick search on the web will reveal a plethora of info. There are also lots of different opinions as to the best way forward, some are based on fact and some seem to be spouted out as sales speel.
It seems to me for starters that there is some confusion with some of the terminology. So I'll briefly run through what they are.
PH is the measure of acidity. Its a logarithmic scale which means that for every 1 unit of measure there is a 10 fold difference. There are many different types of acids which can be held in the water column and PH is a combined measure of them all, i.e. different acids are given off from wood, peat, CO2, buffers etc, etc. Some of the acids are beneficial and some not so.
GH is general hardness and is often also referred to as permanent hardness. It basically consists mostly of calcium and magnesium usually but not always in a ratio of around 3:1 respectively.
KH is Carbonate hardness and is often referred to as temporary hardness. It consists mostly of carbonates which can be used up by rotting matter and therefore tends to fluctuate over time hence its name. It has a buffering affect on the PH to keep it stable. This can be a bit of a double edged sword especially if you are trying to alter the PH with PH buffers.
Ammonia, nitrite and nitrate are by products of the three stages of the nitrogen cycle and should all be kept to a minimum as your already well aware.
TDS is a measure of Total Dissolved Solids which is usually measured with an electronic pen type meter which has a pretty much instant and fairly accurate readout displayed in PPM (parts per million). RO ( reverse osmosis) water has a TDS of 0ppm and is too pure alone to keep fish in. It therefore has to be remineralized before use.
If you wish to start altering water parameters adding more chemicals to change what is already some form of concoction coming out of the tap is not the way to go. The often high levels of buffers will necessitate large amounts of chemicals to counter them and all that does is raise the TDS which many fish are very sensitive to especially Amazonian species. What you therefore need is a blank canvas to start from which is why RO water is often used and then remineralized to suit. If your tap water isn't too bad you may sometimes get away with using a HMA filter instead which is cheaper and more efficient to run and removes all the heavy metal toxins from the water. RO water can be mixed with tap water but why put any possible pollutants that you've just paid to get rid of back in? So it doesn't make sense. It can also be mixed with HMA water (which any RO water filter can also produce just tap off pre-RO membrane filtration stage) which is the way many choose to go or it can be reconstituted to known levels with a mixture of different salts, which is my preferred method..
I mentioned previously how notoriously inaccurate Nitrate testing with home test kits is. A quick glance through any reef keeping forum will bear this out. Also worth having a quick look here:-
[ame="http://en.wikipedia.org/wiki/Nitrate_test"]Nitrate test - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Nuvola_apps_edu_science.svg" class="image"><img alt="Stub icon" src="http://upload.wikimedia.org/wikipedia/commons/thumb/5/59/Nuvola_apps_edu_science.svg/35px-Nuvola_apps_edu_science.svg.png"@@AMEPARAM@@commons/thumb/5/59/Nuvola_apps_edu_science.svg/35px-Nuvola_apps_edu_science.svg.png[/ame]
At best home test kits need to be calibrated against a known reference solution EVERY time they are used and at worst are completely misleading. How can you react to readings that can't be trusted? You may end up changing things that don't need changing or worse miss something that is a threat to your fish thinking that the reading is good.
You have to remember that manufacturers have a vested interest in selling things to uninitiated aquarists (often sales lead to more sales) and far from everything that you read in their glossy brochures and subsequently spouted as gospel is actually true. Next they'll be telling you that Phosphates cause algae.........Mark my words.
The way to know that Nitrates aren't a problem for you is to be safe in the knowledge that your water changing regime is adequate and the the water that you use is ok. You can go online and get water reports from your local authority which will detail the nitrate levels in your area but I would expect them to be ok as most fish will toleate the nitrates themselves without problems within reason.
Its the actual process of producing the Nitrates within the tank that is the real issue here.
Plants consume nitrate (as well as other compounds) and removing plants doesn't remove nitrate. It will actually have quite the opposite effect as removing or decreasing the amount of planted matter will decrease the total amount of nitrates consumed. Plants also have many other needs and aren't by any means a simple solution. I would hazard a guess that you'll run into more problems than you already had if you don't supply the plants with everything they need and expect them to just grow willy nilly.
If plants are unhealthy they will decay and then will cause algae issues and produce large quantities of ammonia. So their health is also of paramount importance if this is the way you intend to go. Again maintaining a healthy planted tank is a huge issue which I can't do justice to in a few lines here but it does offer a very good solution. Just don't think its the easy way forward cause it ain't, far from it.
Chris.
Hi all,
Nitrogen (N) is the macro-nutrient plants need most of (along with potassium K), and it quite likely that the other elements required will be present in sufficient amounts. It was because I wanted a low nutrient planted tank that I developed the "Duckweed index", which is that you feed your tank a small amount of KNO3 and possibly then a total plant fertiliser when the growth of the Duckweed (can be Lemna, but Limnobium is easier to thin) slows and the leaves are noticeably yellow.
Have a look at this one, for more details: <http://www.plecoplanet.com/forum/showthread.php?t=8254>
cheers Darrel
You may not be a chemist L777, but you have covered all the bits that matter really well, and I think this is an excellent summary and I would agree with nearly all of it.
This is the only bit I don't agree with, removing plants does export the nitrate, what you need to ensure is that you leave enough plant biomass to carry on photosynthesising. This is why I suggest using Limnobium (Amazon Frogbit) or other similar floater, it has access to atmospheric CO2 and is easy to remove excess without disturbing the tank.
Nitrogen (N) is the macro-nutrient plants need most of (along with potassium K), and it quite likely that the other elements required will be present in sufficient amounts. It was because I wanted a low nutrient planted tank that I developed the "Duckweed index", which is that you feed your tank a small amount of KNO3 and possibly then a total plant fertiliser when the growth of the Duckweed (can be Lemna, but Limnobium is easier to thin) slows and the leaves are noticeably yellow.
Have a look at this one, for more details: <http://www.plecoplanet.com/forum/showthread.php?t=8254>
cheers Darrel
Hi,
I agree that you'll be removing the Nitrate that has already been consumed by the plants but the overall reduced biomass of plants will lead to a slower uptake of N. If the Nitrate production rate remains the same then there will be an increase in Nitrates overall. That's the point I was trying to make.
Superb advice about using Amazon Frogbit and duckweed. IMO.
Chris.
Last edited:
Hi all,
The availability of nitrogen will almost certainly be the factor that is limiting plant growth. If we added more nitrogen we would get more plant growth, usually until the availability off N becomes limiting again.
In this situation when we remove plant biomass the nitrogen level would start to rise, but any rise will be mopped up by the plant growth. Greater availability of nitrogen leads to more plant growth, which reduces the nitrogen level until it is once again the factor limiting plant growth. It is a self regulating system.
We used to use phyto-filters in the lab, and fast growing plants (either algae or vascular plants) can convert huge nitrogen loads into plant material. This is for Water Hyacinth, Amazon Frog-bit would remove less nitrogen.
From: http://www.springerlink.com/content/jt553064194777gv/
"Productivity and nutrient uptake of water hyacinth, Eichhornia crassipes I. Effect of nitrogen source".
I understand where you are coming from, but I still don't think this is right. The reason is that as soon as you remove leaves, stems or plants more will grow to replace them and make use of the resources available. Think of it like mowing your lawn, you don't eventually run out of grass to mow.
The availability of nitrogen will almost certainly be the factor that is limiting plant growth. If we added more nitrogen we would get more plant growth, usually until the availability off N becomes limiting again.
In this situation when we remove plant biomass the nitrogen level would start to rise, but any rise will be mopped up by the plant growth. Greater availability of nitrogen leads to more plant growth, which reduces the nitrogen level until it is once again the factor limiting plant growth. It is a self regulating system.
We used to use phyto-filters in the lab, and fast growing plants (either algae or vascular plants) can convert huge nitrogen loads into plant material. This is for Water Hyacinth, Amazon Frog-bit would remove less nitrogen.
From: http://www.springerlink.com/content/jt553064194777gv/
"Productivity and nutrient uptake of water hyacinth, Eichhornia crassipes I. Effect of nitrogen source".
cheers Darrel
Hi Darrel,
Would other factors like P and K not have to be non limiting to achieve this extra fast growth of the now trimmed plants? There will also surely be an increased need for micro nutrients if the plants are to remain healthy. I'm assuming that the tank in question isn't having macro or micro ferts added to supplement the plants growth as the sole intention of the tank is to reduce the N in the water column and I'm also assuming that its low tech non CO2 injected. In fact I don't believe any form of carbon is being added to this tank so growth is most likely to be very slow.
I think to evaluate the solution in question that the OP has come up with we need a lot more information about the planted tank being used to reduce the N before the real picture emerges.
Chris.
Would other factors like P and K not have to be non limiting to achieve this extra fast growth of the now trimmed plants? There will also surely be an increased need for micro nutrients if the plants are to remain healthy. I'm assuming that the tank in question isn't having macro or micro ferts added to supplement the plants growth as the sole intention of the tank is to reduce the N in the water column and I'm also assuming that its low tech non CO2 injected. In fact I don't believe any form of carbon is being added to this tank so growth is most likely to be very slow.
I think to evaluate the solution in question that the OP has come up with we need a lot more information about the planted tank being used to reduce the N before the real picture emerges.
Chris.
Hi guys,
You all seem to be having a whale of a time talking about this! It has all been very interesting to follow.
I had not made any choices about how to set it up as I wanted to learn about it all first. My intention was certainly not to do it just for it to be the easy way out.
L117 you asked for more info about the tank-it is 100ltr's that is all the limiting factors-being cheap is not,i just wish to utilise nature.
Respects cole
You all seem to be having a whale of a time talking about this! It has all been very interesting to follow.
I had not made any choices about how to set it up as I wanted to learn about it all first. My intention was certainly not to do it just for it to be the easy way out.
L117 you asked for more info about the tank-it is 100ltr's that is all the limiting factors-being cheap is not,i just wish to utilise nature.
Respects cole
Hi all,
<[ame="http://en.wikipedia.org/wiki/Plant_nutrition"]Plant nutrition - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Question_book-new.svg" class="image"><img alt="Question book-new.svg" src="http://upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png"@@AMEPARAM@@en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png[/ame]>
This was the idea behind EI ("Estimative Index"), light was used as the limiting factor for plant growth, and CO2 and nutrients are added so that their presence is always non-limiting. The light drives the demand for carbon and nutrients and as you raise the light levels you raise both CO2 and fertiliser addition. Plant growth should be near optimal in these conditions, with some plants (Hygrophila, Echinodorus spp. other green stem plants with a large leaf area) growing very quickly (at their maximum growth rate) and others (Mosses, Java Fern, Hemianthus) more slowly (but still at their maximal growth rates).
Where we aren't adding extra carbon or fertilisers and light is lower, one parameter will be limiting and it is usually either PAR light or nitrogen, as these will vary widely in natural situations, whereas global CO2 levels are fairly similar and true aquatic plants will all have evolved at low CO2 levels. If we look at a floating plant like Amazon Frogbit Limnobium, we can definitely discount CO2, as it has access to atmospheric CO2.
We call nitrogen (N), phosphorus (P) and potassium (K) the macro-nutrients, but this is slightly misleading as plants need about x10 as much N & K as they do P. Because orthophosphate (PO4) is added to all the UK's water supply to control levels of heavy metals (PIMS is the term you are looking for <http://www.plecoplanet.com/forum/showthread.php?p=70829&highlight=PIMS#post70829>) it is very unlikely that P will be limiting plant growth in the tank. We can also add a "store" of nutrients if we use a substrate with a high CEC (Cation Exchange Capacity, K+, Mg2+ etc) and AEC (Anion Exchange Capacity NO3-, PO4- etc)
If N isn't limiting plant growth (usually as NO3- from the conversion of the NH3, excreted by the fish, to NO2- > NO3-), K+ may be (which is why I suggested that we add KNO3 first ((39 + 14 + (3 x 16) = 101) (13% N, 38%K)) when using the "Duckweed index".
The only other nutrients likely to be limiting growth are magnesium (Mg2+) (the central element in the chlorophyll molecule) or iron (Fe 2+ or 3+). In this case the situation is slightly more complicated as the problems are usually to do with the interaction with other elements (calcium induced chlorosis and precipitation out of solution), rather than actual deficiency.
After you've added KNO3, if you still don't have a response in terms of plant growth after about 10 days, you could add "Epsom Salts" (MgSO4.7H2O) and Fe EDTA wait another 10 days etc, but if you add the complete macro and micro-nutrient solution you can be sure you will have added the limiting nutrient.
Sorry it is a bit long, but I hope it makes sense.
cheers Darrel
All plants have a finite maximum growth rate, this will depend upon the environment they evolved in. In conditions of high PAR (Photosynthetically Active Radiation), high nutrients, no limit to water availability and warm temperatures, say in the wet tropics on recent volcanic soils, you get a lot of "C4" plants, they use a slightly different photosynthetic pathway to most other plants ("C3" plants) and can utilise atmospheric CO2 more efficiently. A C4 grass like Imperata cylindrica, Maize (Zea mays) or Sugar Cane (Saccharum officinarum), under conditions of light saturation, will have photosynthetic rates (Pmax.) of about double the best performing C3 plant. If we raise CO2 levels this difference declines, as the growth rate of a a C3 crop like Tomato (Lycopersicon esculentum) is CO2 limited. This CO2 limitation is more marked in water, where CO2 is present at much lower levels. Details here:
<[ame="http://en.wikipedia.org/wiki/Plant_nutrition"]Plant nutrition - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/File:Question_book-new.svg" class="image"><img alt="Question book-new.svg" src="http://upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png"@@AMEPARAM@@en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png[/ame]>
This was the idea behind EI ("Estimative Index"), light was used as the limiting factor for plant growth, and CO2 and nutrients are added so that their presence is always non-limiting. The light drives the demand for carbon and nutrients and as you raise the light levels you raise both CO2 and fertiliser addition. Plant growth should be near optimal in these conditions, with some plants (Hygrophila, Echinodorus spp. other green stem plants with a large leaf area) growing very quickly (at their maximum growth rate) and others (Mosses, Java Fern, Hemianthus) more slowly (but still at their maximal growth rates).
Where we aren't adding extra carbon or fertilisers and light is lower, one parameter will be limiting and it is usually either PAR light or nitrogen, as these will vary widely in natural situations, whereas global CO2 levels are fairly similar and true aquatic plants will all have evolved at low CO2 levels. If we look at a floating plant like Amazon Frogbit Limnobium, we can definitely discount CO2, as it has access to atmospheric CO2.
We call nitrogen (N), phosphorus (P) and potassium (K) the macro-nutrients, but this is slightly misleading as plants need about x10 as much N & K as they do P. Because orthophosphate (PO4) is added to all the UK's water supply to control levels of heavy metals (PIMS is the term you are looking for <http://www.plecoplanet.com/forum/showthread.php?p=70829&highlight=PIMS#post70829>) it is very unlikely that P will be limiting plant growth in the tank. We can also add a "store" of nutrients if we use a substrate with a high CEC (Cation Exchange Capacity, K+, Mg2+ etc) and AEC (Anion Exchange Capacity NO3-, PO4- etc)
If N isn't limiting plant growth (usually as NO3- from the conversion of the NH3, excreted by the fish, to NO2- > NO3-), K+ may be (which is why I suggested that we add KNO3 first ((39 + 14 + (3 x 16) = 101) (13% N, 38%K)) when using the "Duckweed index".
The only other nutrients likely to be limiting growth are magnesium (Mg2+) (the central element in the chlorophyll molecule) or iron (Fe 2+ or 3+). In this case the situation is slightly more complicated as the problems are usually to do with the interaction with other elements (calcium induced chlorosis and precipitation out of solution), rather than actual deficiency.
After you've added KNO3, if you still don't have a response in terms of plant growth after about 10 days, you could add "Epsom Salts" (MgSO4.7H2O) and Fe EDTA wait another 10 days etc, but if you add the complete macro and micro-nutrient solution you can be sure you will have added the limiting nutrient.
Sorry it is a bit long, but I hope it makes sense.
cheers Darrel
Hi,
I'm very familiar with the EI index and running high tech planted tanks but I was trying not to bog this thread down to much with all the technical gargon and I know full well that you know exactly what your talking about.
Surfice to say as I mentioned earlier that the plants have to be kept healthy for the OP's solution to work and that it may be a bit more complex than it first appears.
Chris.
I'm very familiar with the EI index and running high tech planted tanks but I was trying not to bog this thread down to much with all the technical gargon and I know full well that you know exactly what your talking about.
Surfice to say as I mentioned earlier that the plants have to be kept healthy for the OP's solution to work and that it may be a bit more complex than it first appears.
Chris.