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new tank set up

Keith

Member
Joined
8 Jul 2007
Messages
27
Hi,

I posted a picture and details of my tank on the original site hosted by Tom Barr but that seems to have got lost so I will start again. Also I cannot find the gallery anywhere so am using photobucket.

http://i92.photobucket.com/albums/l17/k ... G_3562.jpg

The 6' x 2' x 2' tank was set up on June 26th with two plant collections from Greenline with the aim of discovering what would grow for me and so far that seems to be everything. Lighting is two Arcadia 58w Originals on for ten hours, two Arcadia 58w Freshwaters on for eight hours and one Arcadia 58w Freshwater on for five hours. I run a Tetratec 1200 filter with no media, i.e. just for circulation and add nitrate, phosphate and Equilibrium in the small weekly amounts recommended by Tom Barr. There has been some minor rearrangement of plants just to group them.

Stocking is now complete with 60 Cherry Barbs, 10 Juli Corys, 1 Dwarf Chain Loach and 10 Amano shrimps.

This is my first attempt at a freshwater planted tank and any comments and suggestions would be gratefully received.
 
That's looking really good Keith.

I hope you don't mind me adding the image here with
IMG_3562.jpg
hotobucket.com/albums/l17/keithd100_2006/IMG_3562.jpg[/img]

As you've posted this in the low tech bit, I'm wondering whether this is an 'El Natural' tank with soil substrate and no CO2? Or is there some other substrate?
I'm interested in the fact that you're adding macros, AFAIK most natural exponents rely completely on the nutrients from the fish waste. Are you following EI levels of dosing or something closer to PPS? i.e. are you adding high levels with large weekly water changes or smaller amounts of fertilisers and little or no water changes?
 
Thanks Eds that's what I wanted to do with the image.

Sorry about not mentioning the substrate it is 6 bags of Fluorite and about 75 kilos of fine gravel and I must say I was amazed at the amount of root growth when I moved some of the Hygros from the front to the back yesterday.

The fertiliser regime is 1/8 tps KNO3, 1/32 tsp KH2PO4 and 1/4 tsp Equilibrium per 20 gallons added every Sunday. I don't use CO2.

So far I have not done any water changes and do not intend to do any unless I do a major reorganisation of the plants, which I am trying to avoid by moving a few at a time, or something goes drastically wrong. I must admit I was tempted the other day when The water went cloudy and the surface became covered in a brown scum but laziness prevailed and the scum cleared although the green algae cloudiness is still there but somewhat less.

My regime is based on Walstads way of balancing fish waste with plant needs with the addition of small quantities of macros as suggested by Tom Barr to enable the growth of almost all plants. So far it is working although I have no practical experience apart from the last month and am relying on the written word.
 
Sounds good Keith.

All I'd say is that I'd do some testing to check the levels of nutrients in your tank. As you're adding nutrients, both as the salts and as fish food, and not removing them in any way apart from when you trim your plants and remove plant tissue from the tank you may get a build up of the nutrients over time. The only problem is test kits aren't very accurate, but better than nothing!
As your not adding much fertiliser and it all seems to be working well at the moment it shouldn't be a major problem I'm sure, but I'd just keep an eye on it!

If you want to clear up the cloudiness then there are two products that do a great job. The first is nice and simple filter floss that packed into your external will quickly catch any particular matter. The other thing is Seachem's Purigen that is a selective chemical media that clears tank water in no time. As your external's currently empty you could sitck that in there to clear the water too!

Good job and keep us updated as I'll be very interested to see how this method produces long term results.
 
eds said:
Sounds good Keith.

All I'd say is that I'd do some testing to check the levels of nutrients in your tank. As you're adding nutrients, both as the salts and as fish food, and not removing them in any way apart from when you trim your plants and remove plant tissue from the tank you may get a build up of the nutrients over time. The only problem is test kits aren't very accurate, but better than nothing!
.

I would tend to disagree with this as chasing inaccurate readings would lead to more problems than it would solve. Suppose for example that you had false high readings? This would lead you to dose less, possibly causing a limiting condition. If you recall, one of the major points of EI is that you don't have to test. Since we now know that excess PO4 or excess NO3 do not cause algae we shouldn't need to worry about excess bulidup. Additionally, the plants will consume the inorganic sources preferentially. If you are unsure you can always skip a week or more of dosing and see how the plants respond.

As Ed notes, It´s hard to argue with results but I question why no filter media? It seems to me that since you are dosing inorganic ferts you could add media to aid in reduction of NH4 via organic waste. I re-read the non-CO2 EI thread and I couldn't find a reference to deletion of filter media.

Cheers,
 
ceg4048 said:
eds said:
Sounds good Keith.

All I'd say is that I'd do some testing to check the levels of nutrients in your tank. As you're adding nutrients, both as the salts and as fish food, and not removing them in any way apart from when you trim your plants and remove plant tissue from the tank you may get a build up of the nutrients over time. The only problem is test kits aren't very accurate, but better than nothing!
.

I would tend to disagree with this as chasing inaccurate readings would lead to more problems than it would solve. Suppose for example that you had false high readings? This would lead you to dose less, possibly causing a limiting condition. If you recall, one of the major points of EI is that you don't have to test. Since we now know that excess PO4 or excess NO3 do not cause algae we shouldn't need to worry about excess bulidup. Additionally, the plants will consume the inorganic sources preferentially. If you are unsure you can always skip a week or more of dosing and see how the plants respond.

Watching how plants and fish respnd is always a good idea, but Test kits can be useful as long as you accept their accuracy limitations. While you can't rely on them accurately giving levels such as 12mg/l, they are usually accurate when compared to previous tests. For instance I would do a test for Nitrate while everything's doing well and have that 'level' as some kind of bench mark. If you then find subsequent readings with the same kits from the same tank climbing from that benchmark it is a very good inidcation that the level has risen too. The problem is calibrating the kits - the actual reactions taking place are very accurate, it is more often our methods of measuring that let them down.

I don't test often at all, but I'm only advising this as Keith is adding inorganic ferts without the large water changes to dilute them. I know this has been done by a few people far more experienced in it than me, but I don't see how you can keep track of the nutrient levels without testing! How can you know the nutrient requirements of any particular tank without testing, or simply adding slightly more than they could ever use and then doing a large water change to re-set those levels weekly? The whole point of EI, without testing, is that those large water changes are used every week to re-set the levels and stop things getting out of hand. The PPS dosing systems that many have started to use seem a bit more hit-and-miss to me as how do you know how much nutrients your tank needs without calibrating test kits and checking on those levels? How do you know you're supplying enough or too much? One tank's requirements may be vastly different from another. A high tech tank full of stems that needs trimming almost daily will need way more ferts than a lowtech tank with no CO2 and low light filled with crypts and moss. If you aren't measuring how do you know if you're adding too much or too little, and if too little doesn't matterm then why dose? I hope you see what I'm saying here, I'm not trying to be argumentative or awkward I've just never had this explained!!!

I'm definitely no expert on using these kind of fertilising systems and only know this from what I've read, but it seems to me that without large water changes, which Keith isn't doing, it might be a good idea to keep an eye on the nutrient levels. I certainly wouldn't recomend setting a good, target level of nutrients using a test kit and trying to chase that level, just use them to keep an overall eye on things.

I'm also interested in your assertion that, "Since we now know that excess PO4 or excess NO3 do not cause algae we shouldn't need to worry about excess bulidup." While correctly managed nutrient levels don't cause a problem I was always under the impression from every scientific paper and article I've ever read that unmanaged build-ups of these macro nutrients are precisiely what we do need to avoid. Uncontrolled and unregulated use of these chemicals can cause huge problems, that's why everyone uses carefully measured and controlled amounts in their tanks isn't it? Even PPS-Pro where small amounts of chemicals are added without water changes and testing stresses the use of carfeully controlled amounts so that the levels don't build up.
Is there some new research I haven't seen???

Not trying to argue with you, but I'm curious and not convinced at being able to add chemicals without testing or water changes!
 
Hi Ed,
I hear what you are saying and most converts to EI once felt the same way. I know exactly what you are thinking. Seems like another opportunity to guide someone in the direction of Tom Barr's site. The Esimative Index was developed precisely to address these concerns:

http://www.barrreport.com/estimative-index/62-estimative-index-dosing-no-need-test-kits.html

This page is more germane to high light and CO2 injected tanks but later:


http://www.barrreport.com/estimative-index/2817-non-co2-methods.html

This was issued to address low tech tanks. Now, these threads explain the technique of EI but they do not explain the reason behind the development. Somewhere on his website Barr explains his background with the California Department of Agriculture (I believe) and his investigation with nutrient runoff from the surrounding farms into the waterways. As I recall, it was expected that the waterways would be blocked by algae due to nutrient bulidup in the canals, but he found that instead, the canals were being blocked by weeds, not algae. Further investigation and experimentation revealed that in fact, the proliferation of algae, which had long been blamed on high Phosphate and Nitrate levels for years, was actually due primarily by NH4 and other factors unrelated to the PO4/NO3 concetration levels.

Certainly, if the mistakes that we make with our tanks result in the appearance of algae, whatever levels of nutrients are in the water can make the situation worse as the algae will feed on whatever nutrients are available, however the studies that led to the development of EI reveal that nutrient deficiency leads to algae, not nutrient excess. If you become a subscriber to the Barr website you will have access to his newsletters, the most prominent of which are the Nitrogen and Phosphorous articles as well as the more recent Red Algae article:

http://www.barrreport.com/barr-repo...eport-newsletter-january-2006-phosphorus.html

http://www.barrreport.com/barr-repo...eport-newsletter-january-2006-phosphorus.html

http://www.barrreport.com/barr-repo...eport-newsletter-january-2006-phosphorus.html

I'm accutely aware that the suggestion to not worry or to not even care about the NO3/PO4 levels is counterintuitive and provocative, but the truth is that an excess of nutrients is not a causal factor in the appearance of algae. Ones best chance to combat algae is to control the lighting, to ensure that the plants are never nutrient limited, to avoid NH4 buildup and to stabilize CO2 concentrations, whether that concentration is high or low. This greatly simplifies plant husbandry and relieves the aquarist from dependency of nutrient test kits.

I highly recommend that anyone reading this thread subscribe to the Barr Report and gain access to the Newsletters. They are heavy reading but are worth the effort. They will dispel much of the confusion about plant nutrient requirements and water chemistry.

Cheers,
 
Hi CEG,
I think you've slightly missed my point on this. EI relies on large water changes to reset levels weekly. Keith isn't doing these large water changes and that is the reason I advised caution and some way of monitoring levels.
Quoting from Tom's EI article,
"Example #1
Suppose you dose 10ppm of NO3 total to a tank per week. Assume you do a 50% weekly water change. If you do the math, you find out that:

If you assume that NONE of it is used up, you can build up a maximum of 20 PPM

If you assume that 25%of it is used up, you can build up a maximum of 16 PPM

If you assume that 50%of it is used up, you can build up a maximum of 13.3 PPM

If you assume that 75%of it is used up, you can build up a maximum of 11.4 PPM

The concentration will not be 15ppm with 25% weekly uptake because of the previous week’s build up if factored into the equation."

If this was carried on for weeks then that 20ppm would continue to rise and rise and at some point that will cause problems to fish health even if it didn't cause algae.
On page 2 of the Non-CO2 thread Tom also says, "Adding more will do no harm, but the issue becomes one of build up.
Unlike a CO2 higher light method, there are no water changes here.
That is the balance you are dealing with."
This is the problem I am trying to advise Keith about.

Again another quote from Tom's thread on non-CO2 use of nitrate and phosphate,
"The plants grow 5-10x slower, but they do grow.
Now you can test the NO4/PO4 for signs of build up if you calibrate the test kits and they appear to be accurate and dose based on uptake, but since the growth uis slow, generally the plants themselves tell you when you need to dose or how much/add more etc.

Most of you already know what NO3 deficent plants look like or K+, traces etc, so you'll see the same types of things with non CO2, just slower.

So, add 1/4 of the KNO3, 1/8 of the KH2PO4, SeaChem EQ -1/4-1/2 teaspoon each week and if you forget one week, that's likely okay too.

Note plant health as your test guide."
Personally I wouldn't know plant deficiencies that well and for a new comer to do that seems a bit hit-and-miss. If you use a test kit and look for rises in levels then you know your nutients are accumulating and you need to add less! By no means a perfect method, but not too bad don't you think? Used in conjunction with keeping an eye on the plant growth should surely be the best approach then?

As to high Nitrate and phosphate not causing algae, this quote is again from Tom's EI article,
"I truthfully do not know what levels of NO3 and PO4 (for example) cause problems for plants or induce algae in a fully planted tank. NO3 levels above 40ppm can cause fish health issues. PO4 at very high levels can influence alkalinity (KH) above 5ppm-10ppm." (The bold highlighting is mine)

A large amount of experimentation has been done on algae and higher plants looking at their nutrient requirements and preferences and has been published in peer reviewed periodicals. It seems that algae and higher plants may use ammonia preferably, but they can both use nitrate, certainly the green algae that use many of the same biochemical pathways as higher plants. Cyanobacteria and, I believe red and brown algae, use different pathways and I'm not sure what current research says about their nutrient preferences.
I believe the trust of Tom's observations were that they suggested that Higher plants can out-compete smaller algae when stable conditions with an excess of nutrients are maintained, but changes to any habitat tend to favour the more opportunistic colonisers, such as algae, or 'weeds' in the horticultural world.

I'm all in favour of EI and other methods (and have got a rather pointed letter written to me in PFK this month by Jeff Walmsley for my efforts!), indeed I'm currently experimenting with EI on a tank as I finally have time to do the large water changes it entails.
All I'm saying is don't just add chemicals without some kind of way of monitoring or regulating the levels as that could cause problems.
 
Hi Ed,
Sorry if I missed your point and went off on a tangent. The issue may boil down to; "at what point does the built up concentration of these inorganic compounds pose a threat to either fish health or induce algae?"

It seems we've each read the threads and newsletters and come away with slighty different interpretations possibly because we each have individual and different concerns. A possible point of view is to regard these compounds with trepidation and as possible toxins. The extracts that you pulled appear to be within this context. I read the same mathematical excercise Barr offered I my sense was that he was attempting to show that if you were concerned about build up, the water changes in the CO2 injection method would address this concern, however I did not get the impression that he was necessarily concerned about some critical level of build up which would induce algae. My sense was that if algae was induced, for example by CO2 instability, having high built up concentrations would be an obstacle in it's eradication. Perhaps that is a point which is also being missed.

I draw you attention to a recent Barr thread entitled "NO3, NH4 toxicity test on plants and critters"

http://www.barrreport.com/articles/3267-no3-nh4-toxicity-test-plants-critters.html

The results of toxicity tests show that the toxic level of INORGANIC NO3 for the common guppy was something like 4000 ppm, a completely over the top concentration level that we would never see in our tanks. For species such as trout or salmon the toxicity levels were closer to what we see in the tanks but we do not typically keep these species. Marine species were shown to be even more resistant to inorganic NO3 toxicity.

We ought to now be convinced that "... just adding chemicals without some kind of way of monitoring or regulating the levels..." is not going to cause a fish toxicity problem. Besides, we are not "just adding" the chemicals; the concentrations and intervals are specific to the tank size and to the type of tank and to the fish load. If the plants are healthy, and if they are growing then one can be assured that the concentration levels will fall.

Now Ed, really, I have to say that it would totally shock me if you were to insist that you or any beginner could not tell if your plants were growing, even if they grew at a rate 10 times slower than those in a high tech tank. I mean, we are in this hobby to grow plants. We'd better have some idea of what a growing plant looks like. As far as identification of nutrient deficiences, well, OK, fair enough, but I will say that even when I didn't have a clue how to grow tropical weeds I think I still knew that if a leaf was yellow instead of green something was wrong. Here is a link to help out with nutrient deficiency identification:
http://www.csd.net/~cgadd/aqua/art_plant_nutrient.htm

Allright, now lets have a closer look at this Barr extract:

"I truthfully do not know what levels of NO3 and PO4 (for example) cause problems for plants or induce algae in a fully planted tank. NO3 levels above 40ppm can cause fish health issues. PO4 at very high levels can influence alkalinity (KH) above 5ppm-10ppm."

If you were to closely re-examine some of his other threads and newsletters, I'm convinced that you would have a better context of what he is trying to say here. He is not saying that he doesn't know because he hasn't tested, he is saying that he hasn't found a concentration level high enough which caused a problem. In fact, he has tried massive concentration levels but as the journal links in that thread above demonstrates, he hasn't reached levels approaching 4000 ppm. Thats why he didn't know. As it turns out, the toxicity concentration levels for these chemicals are so high as to be practically irrelevant, because if we stick to his dosing schemes we wil never approach these toxic levels.

There still appears to be total disbelief among many regarding the assertion that high levels of PO4/NO3 have no bearing on inducing algae.

Here is an extract from the Red Algae article:

QUOTE
======

A simple test was done by a hobbyist to see if Audouinella was caused by excess levels of PO4 in the plant aquarium.

Table 1 [this tables shows the experiment procedure and results/conclusion]

While not showing what causes a BBA algae bloom, it showed that it could not be caused by excess PO4, therefore there must be some other reason for the algae bloom. Thus aquarists can make a hypothesis, then manipulate and test it to see if their hypothesis was correct or not by isolating the system.

UNQUOTE
========

This is just a tidbit from the newsletter but it shows that high PO4 concentrations actually helps to force BBA into dormancy. The person doing the test actually saw a decrease in algae with increasing levels of PO4. He also saw increased growth as PO4 was increased. Amazing.

This test was performed with a 1ppm PO4 addition repeated 10 times so there is no data regarding actual build up concentrations. I myself have run tanks in the 5-10 ppm PO4 and with 70 ppm and higher NO3 (high light). I had no toxicity problems and I only got into algae trouble when I got lazy (and stupid) with the CO2 (i.e, running low without paying attention). It should also be noted that this was a Discus/South American tank.

Again, I have to declare that when you're running these concentration levels and you make an algae mistake, you make THE algae mistake and you are in trouble because your tank will be ravaged as if the Red army were rolling through it. I reiterate though that these concentrations do not cause the algae.

I would also like to point out that the reason Barr advocates the large water changes is not because is so concerned about the INORGANIC chemical buildup, but because of the ORGANIC NH4/NO3/PO4 buildup caused directly as a result of the flora and fauna growth/metabolism. I believe that the colossal differences between organic and inorganic sources of nutrient buildup is still poorly understood, and it may even be the reason that hobby grade test kits are so diabolically inaccurate. When setting up a tank he advocates 3X weekly water changes of 80% or so. This is to directly combat the NH4 buildup as a result of the organic nitrogen cycle. This is the real killer in our tanks, NH4, not inorganic nitrate/phosphate.

In a non CO2 tank, you can do with only inorganic nutrient sources but Barr has proven that the plants have a preferential uptake of the inorganic sources and, at certain NH4 concentrations, the plants prefer inorganic nutrients over NH4. The implication of this is tremendous because that means the plants will allow NH4 to linger which means the algae have a better chance of getting at it.

So in fact Ed, you have a point in that if there are high levels of inorganic PO4/NO3 and if you do not have enough nitrifying bacteria the NH4 will likely induce the algae. This is completely different though than blaming the PO4/NO3 for the algae. This is why I am of the opinion that filtration is critical in the non CO2 tank in which you will dose ferts. I feel the organics should be left to nitrification and inorganics fed to the plants. I have never properly run a non CO2 tank though so I can't actually prove this opinion.

My contention therfore, based on study of the Barr articles/threads, as well as from my own empirical experience, leaves me in no doubt that one never needs to test for these particular chemical concentrations since they pose neither a threat to fauna, nor can they be implicated as a cause of of algae.

Now, if one likes to test, or if some level of comfort is derived from testing, then by all means, one should test. I caution beginners though, that it is very easy to start to rely on testing instead of having your focus on observing and learning about the very specimens you are trying to grow. The reason I dislike testing so much is because it makes us draw conclusions due to correlations instead of allowing us to understand the complex reasons. Barr concedes to testing in that extract because he has a comprehensive and fundamental understanding of causes.

Cheers,
 
I think the point is not algae but fish health. This is why EI has large water changes. If there is no risk and no need to test due to the high water changes. If there are no water changes then there is obviously risk and need to test. Makes common sense to me and I assume Ed is on the same school of thought on this one.

Algae is a bane but not a problem in a tnk so there is never any need to do anything to avoid it. We worry about algae due to the aesthetics we are trying to achieve.

Andy
 
CEG I agree with a lot of your points and hope you see the sense in mine. Do bear in mind though that Tom's observations and experiments are one point of view. There are a lot of others who have studied similar things and come to different conclusions. That doesn't mean that anyone is necessarily wrong, but merely gaining different insights from similar result; a fairly common thing in science!

Again though you quote that, "the water changes in the CO2 injection method would address this concern". My point that started this whole, really stimulating and interesting debate off was that Keith isn't doing water changes and he should keep an eye on the possibility of a nutrient build up!

I didn't mean to suggest that Tom thought a high nutrient level WOULD cause lagae, merely that, with everything he has said, he wasn't sure it wouldn't. The statement I quoted suggested quite strongly to me that he thought that was a possibility.

One of the studies he quotes about the toxicity of nitrate makes it very clear that they are talking about those high levels as short term exposures and, to quote Camargo, Alonso and Salamanca, "Nitrate toxicity to aquatic animals increases with increasing nitrate concentrations and exposure times. In contrast, nitrate toxicity may decrease with increasing body size, water salinity, and environmental adaptation. Freshwater animals appear to be more sensitive to nitrate than marine animals." The quoted levels of 4000ppm therefore seem a little excessive to me as a long term level. Indeed the same paper quotes the highest levels for guppy fry as being 191mg/l of N-NO3, therefore levels of around 840 mg/l NO3. Way below the 4000ppm figure. It does not state whether these are long term or short term exposures as far as I can see.
Please bear in mind the figures they quote are LC50 figures. Those are figures where 50% will die. Hardly a recomended effect in our tanks.

Please note that I'm not suggesting that anyone would be unable to tell if their plants were growing or not, but how do you know what is causing the lack of growth? The great thing about the EI method is that it supplies all nutrients in slight excees while preventing build ups with large water changes. It endeavours to make sure that the plants lack for nothing. But if you find a problem with plant growth do you simply add more of everything? What if the problem with plant growth is due to low CO2 or low light? Adding more nutrients will not help. I'm also colour blind, as are over 5% of men, and telling whether a leaf is yellow or pale green is very hard for me - I like to rely on tests for this reason, but accept, and work within, their limitations.

I completely agree with the points about the possible differences between organic and inorganic forms (A complete misnomer, but I won't go into that here) of chemicals. From a few observations, plants do seem to prefer the simpler forms, probably to do with their simpler nature and the ease of assimilation (totally unproved AFAIK) but as you suggested this may cause problems with a nutrient build up. To assume that this is totally down to a so called 'organic' forms is rather a leap of faith, but as so little study has been done this may be true. It has NOT been 'shown' but merely suggested as far as I can see so far. I have certainly drawn the same conclusion as Andy that plants will assimilate NH3 ions preferably to even 'inorganic' Nitrate, as it takes a less expensive molecular pathway to utilise it. Part of the supposed benefits of EI AFAIK are that they increase plant growth so those plants are more able to quickly utilise NH3 ions and deny the algae them. This is not the same as saying that high nutrients don't cause algae.

For the sake of completeness I'd like to add that NO3 is Nitrate and N-NO3 is Nitrate too, but measured as the amount of Nitrogen (N) in Nitrate (NO3) Therefore N-NO3 needs to be mutliplied by 4.4 to get the total level of Nitrate as that is only measuring the bit of Nitrate that is Nitrogen.

I'd just like to say that the logic and 'safety' (for want of a better word) of the EI system is evident from it's basic concept with large water changes, but to take it further requires, IMHO, much further study and research. Instability of any sort seems to be an excellent way of encouraging algae as they are opportunistic organisims and those kind of organisms do well wherever there is instability in any ecosystem.

Enjoying this, good healthy debate is the best! I hope you are too!
 
eds said:
I'd just like to say that the logic and 'safety' (for want of a better word) of the EI system is evident from it's basic concept with large water changes, but to take it further requires, IMHO, much further study and research. Instability of any sort seems to be an excellent way of encouraging algae as they are opportunistic organisims and those kind of organisms do well wherever there is instability in any ecosystem.

Enjoying this, good healthy debate is the best! I hope you are too!

Hi Ed/Andy
Yes, I find this is fascinating discussion because issues arise that perhaps one would never have considered. It also helps to crystalize the concepts and to help focus. It would never have occurred to me that observation would be impaired as a result of color blindness. This raises the question though of why observation of the test kist color changes aren't also affected. It would seem to me that being color blind would provide greater incentive to avoid using a test kit.

As I alluded to in an earlier post, I absolutely see the sense in the points you made because I once held the very same ideas. Remember it's not that I am opposed to knowing the nutrient concentration levels. It's that I became disillusioned with hobby grade testing. These kits simply do not tell the truth. Although I agree with your statement about different insights gained by each person studying a phenomenon, I have a slightly more stringent requirement of science. Science must tell us the truth of a matter. It's all well and good to have different insights because that helps to find different avenues to the truth. Ultimately though, there can only be one truth. There may be different ways to apply that truth but someday, regardless of the various insights, we must all converge on that truth.

Yes, many have studied this issue and have arrived at different conclusions. The question I have is why are there different conclusions? Should we accept that there are different conclusions for the same phenomenon? My instincts tell me "No".

As you say, Keith is not doing a water change thus the threat of nutrient buildup. At the risk of being repetitive I'm using the NO3 and PO4 newsletters as my only references. The article states that the concentration of each nutrient source (let's restrict it to Nitrogen for the moment - organic NO3, inorganic NO3 and NH4) will determine the uptake priority. Andy, I see that you read the NO3 article but page 2 bottom paragraph clearly states that;
"...There is also a distinction between Dissolved organic (DON) and dissolved inorganic nitrogen (DIN) in the water column. Plants can use the DIN but have trouble with the DON fraction. While there is some scant evidence that plants will use a small amount of NO2-, it is generally a toxic anion that plays an insignificant role in our tanks after a period on new tank cycling..."

Additionally, page 11 bottom paragraph states;
"...Figure 3 shows NH4 preference at levels between 2.0 to 0.5ppm and NO3- preference when the NH4+ is less than 0.5ppm..."

I interpret these results to mean therefore that at normal levels the uptake priority would be;
1) Inorganic NO3
2) Organic NO3
3) NH4

Unless the tank is being cycled the NH4 concentrations should be almost immeasureable so it should stay at priority 3. If there are newer studies that dispute this I'd love to read them.

In any case, let's say that we do not dose and that the fish supply the NO3. In the absence of inorganic NO3 the plants use the DON at a slower rate. With a slow uptake rate no water change it really not clear to me what DON concentration levels we would typically see. I'm sure it would depend on biomass, however if we now start to dose DIN growth rate should increase as well as DIN and DON uptake as a result of;
1) DON accessibility
2) DIN/DON uptake due to increased biomass from growth

I guess what I am trying to say is that theoretically, we shouldn't need to worry so much about the concentration buildup because increased growth should mitigate the buildup. More plant biomass -> more NO3 usage. Lets say you dosed DIN until after some months you doubled the plant biomass, then suddenly stopped dosing. Now, twice as many plants (effectively) are forced to uptake the remaining DON. It wouldn't be a stretch to imagine that flora and fauna may not be able to supply enough DON for the new biomass levels. This may not be strictly true since more plant biomass will also generate more DON due to more leaves decaying etc.

I think you are correct about the toxicity studies in that effectively they added DIN untl they started to note negative effects. Those articles are also heavy reading and I could not find difinitive statements regarding the amount of time of which the fauna was exposed.

The point you raised "...how do you know what is causing the lack of growth?" is a valid one. These are the practical dillemas faced everyday. Since each tank is disctinct there is no one answer to fit all, however, if you did just add a bit more of everything and saw no increase as a result can you not then conclude that poor growth isn't due to lack of nutrients? I mean, isn't that a good scientific and logical conclusion? And if you could be confident that adding a bit more of everything in order to check the theory would not result in toxicity or algae would that then not free you to have a more effective troubleshooting?

Regarding the long term effects of exposure, I can only offer that I have kept fish to their complete life cycles, have bred sensitive species in the same EI tank and have raised them to adulthood without any observable effects so I'm pretty confident that the long term effects are also not a concern.

Cheers,
 
Hi,

Four months later and time for an update.

Still no water changes and the regime is the same except there were no macros added while I was away for two weeks.

The plants have decided which ones want to grow and the rest gave up although the vallis is still struggling on.

As can be seen in the close ups I have an algae problem (hair algae?) which I am controlling by hand a couple of times a week. It is mainly on the back glass and grows to a foot or so long. Anyone got any ideas?

I quite like the present arrangement but as always your comments will be gratefully received.


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beautiful tank, i love this natural approach I hope one day that I may get confident enough to try this way :?

Can I ask where you got the Alabama Swampwood, had a look at your site, that wood is stunning. I'm a real wood fanatic

Regards
JOHNNY
 
Thanks Johnny,

That particular piece came from Taunton Aquarium Centre. It just hit me in the eye when I walked in.

I've got another lovely piece from Leicester Aquatics which has been soaking since November and which I will be using tomorrow night when I re-scape my other tank - watch this space!

If you really want the natural approach I say just go for it. This tank was was the first freshwater I have ever had.
 
Thanks for that, have emailed them, non in stock at the moment :(

I think i need to finish reading Diana Walsteads book, still not 100% on the ratio's of plants to fish etc so I can go ahead, will only be on a small scale though,40/90ltr.

Any more tips?

Cheers
JOHNNY
 
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