High nitrate, tried sulphur?

Discussion in 'Chemical Filtration / Low Nutrient Systems - LNS' started by Mo_G, 8 Mar 2010.

  1. Mo_G

    Mo_G MASA Contributor

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    I have tried this a number of time and have found this to work quite well if done correctly. So read, read and read again until you fully understand before trying it. Within 3 days it should start reducing your nitrates. the article was given to me by Marc Langouet.

    The autotrophic biodenitratation on sulphur in marine aquarium

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    By Marc LANGOUET

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    [FONT=&quot]1°) A biodenitrator why? [/FONT]
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    [FONT=&quot]To really understand how this idea was born, it is necessary to remind the aquarist context in the beginning of the years 1990. At that time all French aquarists were confronted with the problem of the constant nitrate rate increase in their aquariums. The Berliner so-called method was not practically known in France as AQUARAMA published the first paper on it in 1991 (D.STUBER). The most widespread solution to eliminate these nitrates that made almost impossible the conservation of the invertebrates that we began to find on the market, was water changes. [/FONT]
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    [FONT=&quot]It could be achieved either by a massive change of an important quantity of water, with the risk of a important disturbance in the aquarium, either by the very fashionable method at that time of the continuous « water drop change » on which it could be found very numerous publications in the aquarists magazines of the beginning of this decade. For my part I changed 30 to 50% of the water of my tanks every Saturday... [/FONT]
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    [FONT=&quot]However these methods present major inconveniences ; they require the use of a water in which the nitrate concentration is the lowest possible, or it becomes almost impossible to get a low content of nitrate in the aquarium. It is necessary to add otherwise that at this time, the use of the osmosys was again very little widespread in aquaristic world, and that even today where they spilled extensively in reef aquarist, we never have to forget that they don't eliminate all nitrates (when they eliminate them!), and that in some areas the concentration of nitrate in the tap-water being high, the preparation of a synthetic sea water from osmosed water can sometimes lead to nitrate rates in the range of 5 to 10 mg by liter (NB All values of nitrate rate in this article are expressed in mg / liter of NO3 nitrate and not in mg/liter of N-NO3). [/FONT]
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    [FONT=&quot]Besides the method of the water change consists in throwing a important quantity of water just to eliminate only one ion : the nitrate. I have searched therefore very soon a much more selective method eliminating these bothersome ions and I orientated my investigations toward the biologic eliminations processes of the nitrates by breathing nitrate in poor oxygen situation and transformation of the nitrates in sparkling nitrogen. [/FONT]
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    [FONT=&quot]At that time some rare companies sold systems constructed to achieve this biodenitratation in heterotrophic way that means with regular additions of an organic carbon source ( generally glucose or a derivative of glucose) in order to feed the heterotrophic anaerobic bacteria. These bacteria take the necessary oxygen for their breathing and for the oxidation of the organic carbon serving them of food, in the nitrate ion, that they reduce at the sparkling nitrogen state, and permit an elimination of the nitrates of the closed system that constitutes the aquarium. [/FONT]
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    [FONT=&quot]This method works very well but it presents two major inconveniences: it needs, for maintaining the biologic reaction, to feed the bacteria very regularly, and to calibrate this addition of carbon in an enough precise quantity. Indeed, too little carbon drives to a partial reaction and the continuous production of nitrites, whereas too much carbon drives to a too reducing environment, that results quickly in a characteristic odor of rotted eggs due to the production of sulphides. This addition of carbon must be of course adjusted in relation to the water flow in the reactor and to the concentration in nitrate of the water to be treated, what complicates the problem furiously. Besides the system is relatively little tolerant in relation to the flow rate, especially because to practice this nitrate breathing, the heterotrophic bacteria must be maintained in conditions of low content in dissolved oxygen, and also because for a certain flow rate of water it becomes difficult to achieve the reaction, even by important glucose addition,. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Finally the starting of the reaction need enough time ; it is necessary to wait about four to five weeks before being able to produce a water without nitrate, and during the last three weeks of the process there is a continuous production of nitrites. [/FONT]
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    [FONT=&quot]End 1990, I contacted the professor Guy Martin specialist in the water treatment in the Engineer National School of Chemistry in Rennes where I finished my chemist engineer studies in 1978. He had himself experience of an autotrophic biodenitratation process on sulphur for potabilisation of fresh water destined to the adduction network. However he ignored completely the possibility to use the same process in sea water and the impact of such a process on fauna and flora in a marine aquarium. [/FONT]
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    [FONT=&quot]2°) My first experience [/FONT][FONT=&quot][/FONT]
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    [FONT=&quot]After having hesitated for a long time until September 1991, I decided finally to make the experience on a tank of 200 liters with marine fishes, superior algaes like caulerpas and sea urchins. I build a cylinder shaped reactor with 40 cm in height and 7, 5 cm in diameter filled with 2 kg of sulphur, and in which I by-passed a small part of my EHEIM filter. The initial flow rate was 10 drops/minute (about 60 ml/h). Two days later I noted that the content in nitrite at the exit of this column was very important in the range of 5 mg by liter of N-NO2 ( measurement unit of the TETRA test, equivalent to 16 mg/l of NO2) ; it had not any impact on the aquarium himself due to the very low flow rate, allowing the small quantity of nitrites produced to be oxidized in nitrates by the aerobic filtration of the aquarium. The third day the nitrites at the exit of the reactor fell again to 0 and then I have been able to measure the content in nitrate of the produced water that was also at 0; it is important to note that in the tank the content of nitrate was about 37 mg by liter when the experience started. Nitrite and nitrate having fallen to 0, I could increase the flow rate then gradually, first of all to 30 drops/mn then l l/h and finally until 10 l/h, without seeing the nitrites nor the nitrates re-appearing at the reactor exit. [/FONT]
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    [FONT=&quot]On the other hand water coming out the reactor proved to be very acidic for a sea water as the pH was in the range of 6 to 6,5. I added a height of 10 cm of maerl therefore in top of column to buffer this water, which gave me a much more better pH. However because of the produced acidity and the nitrates having come down again very quickly to the range of 10 mg / l in the tank, I decided to reduce the flow rate to avoid to lower too much the pH of the water in the tank. I worked then in a range of flow rates being located between 1 to 2 liters per hour, that I adjusted by crushing the tube entering the reactor with a Mohr clip. [/FONT]
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    [FONT=&quot]This experience continued many months on the same tank that always works 10 years after with the same reactor, even though this one has been stopped some weeks at the time of a move from Paris to Brittany. The experience having proven to be positive and without negative consequence on fauna and flora in the tested aquarium, I decided some months later in 1992 to set it to a tank of 240 l populated with soft and hard corals (LPS), and then with SPS that began to be available on the market at that time. [/FONT]
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    [FONT=&quot]This second reactor that I constructed was in all identical to the first one with the exception of the part destined to buffer the pH which was constituted with a second identical column to the first but full of maerl in order to get at the exit practically the same pH as with the water entering in the sulphur reactor. [/FONT]
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    [FONT=&quot]Different experiences have been done end of 1994 on domestic " aquariums " of variable initial nitrate content, and no negative consequence having been noted, but on the contrary, the system having proven quickly very efficient to maintain a low nitrate rate in aquariums highly fed, I decided end 1994 to communicate on the method in order that anybody can use it. [/FONT]
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    [FONT=&quot]A first pilot experimentation has been done in the aquarium of the Musée des Arts Africains et Océaniens in Paris. This positive experience incited Michel HIGNETTE curator in this aquarium to set it on the commun sea water circulation of the aquarium (45 000 L) where it lowered in some weeks the content of nitrate from 300 mg/l to about 10 mg/l. [/FONT]
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    [FONT=&quot]When then in May 1996 I took the technical and scientific management of the « Grand Aquarium » of Saint - Malo, I set very quickly reactors with diameter 315 mm and 2 m height. The only modification in relation to the first experimentations was the use of sulphur in balls with diameter between 3 and 5 mm used in wine industry. Indeed the first experimentations had been made on sulphur in hammer broken pieces which produced an irregular granulometry sometimes driving to cloggings of the column. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]These balls of sulphur allowed easier water flow without clogging. The column of sulphur is followed with one or even better two columns of maerl of identical volume and geometry. An article has been published in 1996 on the occasion of the convention of the EUAC (European Union of aquarium Curators): « Elimination des nitrates par filtration biologique autotrophe sur soufre en aquariologie marine » by Michel Hignette, Benoît Lamort, Marc Langouet, Sebastian Leroy and Guy Martin. [/FONT]
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    [FONT=&quot]3°) The biodenitrator on sulphur: why today? [/FONT][FONT=&quot][/FONT]
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    [FONT=&quot]Today in reef aquarium there is two main methods : the so-called Berliner method, probably the most widespread in Europe, and the Jaubert method that encourages the reduction of the nitrates in nitrogen by heterotrophic anaerobic process in the tank itself, through a deep sand layer on a plenum. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]These two methods give both excellent results, however it can happens that for a reason or another nitrates rise above the desirable level (due for example to a too slow foam skimming, or even too strong foam skimming in the case of the Berliner method): in this case the autotrophic biodenitratation on sulphur could be applied in an occasionnal or continuous way to recover a suitable nitrate rate. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Otherwise, it is necessary not to forget that the reef aquariology even mainly being oriented toward the photosynthetic corals, has a huge progress to make with regard to the non photosynthetic corals. These corals need to be fed heavily and generally are low illuminated what often makes inapplicable the two previous methods without a technical complement to solve the problem of the nitrates specifically. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Last but not least it is important not to forget that the marine aquariology is not only limited to reef aquariology but that one can be interested by the realization of tanks for fish only, or with many fishes plus some invertebrates that generally do not accept high level of nitrate. Finally I would mention the happy owners of big tanks of several thousands liters and the public aquariums where the Berliner method is not very popular due to difficulties to use it on big volumes. [/FONT]
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    [FONT=&quot]4°) Biochemistry of the autotrophic denitrification on sulphur. [/FONT][FONT=&quot][/FONT]
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    [FONT=&quot]Facultative anaerobic bacteria as Thiobacillus denitrificans have the possibility when they are under low oxygen coditions (hypoxic situation) to « breathe oxygen atoms » present in the nitrate (or nitrite) ion and to transfer them on the S sulphur or its derivatives (S -, H2S,...) to oxidize them in sulphates; it is the so-call nitrate breathing. [/FONT]
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    [FONT=&quot]As far as I know, the reaction stœchiometry has never been studied in sea water where the method had not been experimented before, although some very recent works seem to show that the process has been observed in the marine environment. On the other hand in fresh water and on sulphur it has been studied, and the following stœchiometry has been proposed: [/FONT]
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    [FONT=&quot]11 S + 10 NO3 - + 4.1 HCO3 - + 0.5 CO2 + 1.71 NH4+ + 2.5 H2O--- > 0.92 C5H7NO2 + [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]11 SO4--+ 5.4 N2 + 9.62 H+ [/FONT]
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    [FONT=&quot]It is necessary to note for those who are not familiar with these biochemical (and non chemical) reactions, that these are approached equations; C5H7NO2 represents the biomass. Sulphur acts as " food " (it brings the energy) and as it is non soluble in water, it is at the same time a colonization substrate for the bacteria: all the interest of this method is that the bacteria have permanently a source of energy without having to feed the system, nor besides to have to add whatever it is. Sulphur is consumed very slowly but many monthes are necessary to notice it. [/FONT]
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    [FONT=&quot]In sea water the presence of the carbonated sea buffer reacts with H+ and certainly modify the reaction that, globally, has been experimentally proved to produce carbon dioxide and not to consumme it : indeed the degasing of the acidic water produced lead to almost teh same pH as the sea water before reaction. [/FONT]
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    [FONT=&quot]5°) Setting the autotrophic biodenitratation on sulphur [/FONT]
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    [FONT=&quot]a) The reactor [/FONT]
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    [FONT=&quot]For a water of which nitrate rate is lower than 50 mg per liter, it can be applied the general rule that the volume of the sulphur reactor expressed in liter must be equal to about 1% of the volume of the tank. Why expressing it in volume and not in mass? Simply because when you want to built a reactor you need to know its geometry, which is governing the construction, and not the mass of sulphur. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]However it can be indicated that sulphur in balls of average diameter between 3 and 5 mm have a density in the range of 1,15 that permits to estimate the weight of sulphur to buy. Of course another granulometry will have another density. To this topic I advise against using sulphur in powder considering its very big propensity to clog. [/FONT]
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    [FONT=&quot]In the first centimeters of the sulphur column water starts with unloading itself of its oxygen, indeed the facultative anaerobic bacteria start with breathing the oxygen dissolved, what is less energy consumer for them than breathing nitrate: as it is this second breathing that is interesting for us to eliminate the nitrates, it is necessary to built a sufficiently long column so that the course of water in anaerobic condition is sufficient. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]On the other hand a too large column in relation to its height facilitates preferential paths of water through sulphur, water having tendency to use the shortest path to go toward the exit of the reactor. In the case of preferential paths, due to no-oxygen areas parasitic reactions could occur in a part of the column. Even though the biologic reaction is tolerant enough in relation to the content in oxygen dissolved, too elevated oxygen content doesn't allow the nitrate breathing and too low content allows settlement of other bacterias that those required, what can lead to the creation of very reducing areas in some particular cases producing some sulphides with characteristic odor. [/FONT]
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    [FONT=&quot]To avoid this it is sufficient that the column of sulphur is bathed by the most homogeneous and most regular possible water flow: you can get it very easily in using a column which height is at least five times more than the diameter, and by making water circulating vertically from bottom to top of the column . In the initial step of a reactor when working with water at a high level of nitrate, the production of sparkling nitrogen can be higher than nitrogen solubility in water. In this case you will see nitrogene gas inside the reactor. This gas, considering the very low flow of water in this reactor and the numerous obstacles that the balls of sulphur constitute, risks to be trapped inside if the flow of water doesn't help it to leave. The best solution is therefore to have a vertical flow of water from bottom to top because the natural tendency of gas is to go up. [/FONT]
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    [FONT=&quot]Such a reactor with sulphur at 1% of the tank volume will be very difficult to launch, or even impossible to launch if the initial nitrate rate of the water is more than 50 mg per liter. In this case it will be necessary to choose between the construction of a more important volume reactor (for example 2% in sulphur if the nitrate rate is between 50 and 100 mg/litre but it has been proved to be too big when nitrate will have decreased below 50 mg/l), or it will be necessary to decrease previously the nitrate rate below 50 mg/l through an important water change. Indeed it is always possible to start at 100 mg/l nitrate with a sulphur volume of 1%, but it will need to reduce tremendously the water flow, what could make impossible, in an aquarium where you will continue to feed and doing so to built nitrate, to succeed in lowering the nitrate rate in a meaningful way. [/FONT]
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    [FONT=&quot]b) The columns of calcareous substratum [/FONT]
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    [FONT=&quot]To avoid the production of a too acidic water I recommend you to drive water at the exit of the sulphur reactor in a second or even better a third identical reactor as the sulphur one, both in geometry and bottom to top water direction, but full of calcareous substratum: the volume of the calcareous substratum that will fill these reactors will be therefore equal to one or rather twice the volume of sulphur. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]In all experiences that I drove personally Maerl was used as calcareous substratum. Some have since used also other substrata: the essential is to have a sufficiently fine granulometry to have enough surface exchange, without reaching a too fine granulometry that will be inevitably source of clogging. It is necessary not to forget that the relatively important acidity of the water produced by the sulphur reactor will drive sooner or later to the reduction of this calcareous substratum in fine particules, and then in mud in which water could not pass anymore; for this reason my preference goes to a variable granulometry from 1 to 5 millimeters. It is of course necessary to use as in all limestone reactor a substratum not bringing too excessive formation of bothersome ions at the time of its dissolution; I especially think about the phosphates but also about heavy metals. [/FONT]
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    [FONT=&quot]c) The flow rate[/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]During the initial phase of starting the biologic process, the flow rate must be adjusted the lowest as possible and in any case must not exceed a drop per second and by fraction of 2 Liters of sulphur (says 2 drops per second remains acceptable for a 4 Liters sulphur reactor). [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]This point is especially important and seems to have been badly understood when I began to communicate on this method. There is production of nitrites during the starting phase, that means generally in the first three days after setting the water flow in the system. If the flow rate is enough low as recommended previously, this small production of nitrites doesn't have any impact on the tank, but this assertion is not of course true if you work with too strong flow rates. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Otherwise in the initial phase of development of the anaerobic bacteria, it is especially important that the biggest possible part of the volume in the sulphur reactor is under hypoxic condition so that the bacteria get settled as soon as possible; for getting this a very low flow rate is also required. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Once the bacterial flora is well established, one notes that the water coming out of the reactor will lower its nitrites rate suddently, generally within in some hours. If the conditions recommended before are respected it occurs generally between the 3rd and the 5th day after the starting, and it is only at that moment that you can increase gradually, in some days, the flow rate until reaching the cruise speed that be can estimated at about 1 liter per hour and by liter of sulphur. If I give a aproximated flow rate value and not a precise value it is simply that every aquarium is different and that according to the precise initial nitrate rate, the daily contribution of food, the own tank capacity to reduce the nitrates in nitrogen, it cannot be possible to give a precise value for the parameter flow rate; some measurements of nitrate rate in the following weeks and months will permit, according to the own parameters of the tank to determinate a flow rate for cruising. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Please note that if you increase the flow rate too quickly depending on nitrate rate and sulphur volume you could see the nitrites and nitrates reappearing at the reactor exit due to an incomplete reaction. On the other hand it is rare to produce some sulphides (characterized by an odor close to the rotted eggs); it only occurs in the case of extremely low flow rate in the reactor (to the limit of the stopping, for example by clogging) or in the case of preferential paths driving to the non irrigation of a part of the reactor and the realization of an anoxic area (that is to say completely oxygen free); the production of sulphides is without consequence as they are always bound to a very low flow rate and therefore that their negligeable quantity is re-oxydated in sulphate in the tank. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Their presence is especially rare because Thiobacillus denitrificans in anaerobic condition is itself able to oxidize the sulphides in sulphate as it does for sulphur. On the other hand at the time of a re-initiating the flow after clogging you need to let the time to the bacteria to make this transformation and if not some sulphides can come out of the reactor in small quantity. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]d) How to adjust the flow rate? [/FONT][FONT=&quot][/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]To flow the reactor, water can be send directly by a pump placed in the aquarium, or by a by-pass on a already existing water tube. It is necessary not to forget that such a column of sulphur, plus one or even two columns of calcareous substratum, represent nevertheless a non negligible load loss, especially after some months of working, because the biomass can come to clog partially the sulphur column and especially the limestone columns where the attacked substratum will produce fine particles as explained previously; for this reason it is necessary to be able from time to time, when the flow rate seems too decrease, to flow higher rate of water under pressure only during some seconds to « clean » the system. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]You can consider approximately that a pump with a flow rate between 100 times an 200 times the sulphur volume per hour must permit this operation (200 to 400 l/h for a 2 liters sulphur) even though of course it is not the flow rate of the pump that has to be taken in account but its ability to send water under pressure. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]It is better to get the day to day low flow rate by « crushing » the plastic tube entering the reactor with a device like clip of Mohr (EHEIM for example), at least for the small reactors requiring very low flow rates. It is better to crush the entering tube than the exit to facilitate the possible exit of gas. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Although I never used it personally, it seems that the peristaltic pumps, although more expensive, would also permit to assure this function. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]e) The decrease of the nitrates in the tank [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]When the reaction has started the nitrate rate is going to lower relatively quickly in the aquarium; however the decrease won't be linear but exponential as the water without nitrate at the exit of the reactor will be remixed with the water of the tank. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]On the other hand the food for the animals will continue to produce nitrates that will oppose the decrease of the nitrate rate in the tank. It is therefore very difficult to be able to calculate how long it will take for the tank to recover an acceptable nitrate rate; in general it needs some weeks and then again you can decrease the flow rate of the reactor in order to just maintain the aimed nitrate rate. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]The operating bacteria are able to work even with very low nitrate content and therefore it is possible to reduce the nitrate rate in the tank to non measurable values (lower to 0.5 mg /l) through aquariophily tests. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]It is necessary not to forget that the system is producing calcium by calcareous substratum dissolution, so to let the reactor operating at too elevated flow rates can lead to very important calcium rates in the tank: sometimes it has been observed calcium rates twice the natural sea water amount and even though personally I didn't ever record negative consequence of such rates, some noted that calcium above 800 mg per liter can produce calcic precipitations in the aquarium. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]f) The sulphates [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Thiobacillus denitrificans are able to oxidize all derivatives of sulphur (S, S -, H2S...) in sulphates. The question that comes immediately is what about these sulphates in a closed tank ?[/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]It is necessary to note first of all that the sulphate concentration in sea water is about 2,65 g per liter (900 mg/litre expressed in sulphur in the sulphates). Even though the reduction of a nitrate ion in nitrogen produces 1,1 sulphate ions, it is necessary to have processed a important quantity of nitrate to begin to increase in a very meaningful way the rate of sulphate in the aquarium. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]Besides, Michel HIGNETTE curator of the Aquarium du Musée des Arts Africains et Océaniens in Paris noted at the time of recent studies that the sulphates were trapped by the limestone columns destinated to buffer the water acidity and that the sulphate rate in a tank working in the recommended conditions remained practically steady on a long period. The calcareous substratum, becomes gradually mud by acidic attack, and has to be replaced after some time of use (generally long enough), and so the produced sulphates are eliminated. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]g) The KH and the pH [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]On an aquarium where the system is used at a normal flow rate to avoid the rise of nitrate, you can note a stability of the KH and the pH on long periods (several months or even years) without changing water. On the other hand when you work with elevated flow rate for example in order to decrease quickly the nitrate content of an aquarium where it was too much, it is necessary to monitor the KH and the pH that can show a tendency to the decrease particularly the KH if you have built too small calcareous substratum columns. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]The pH measurements at the calcareous column exit permits easily, when it is low, to anticipate the pH and the KH decrease in the tank. Note that an energetic degasing (by air bubbles) of water coming out of the sulphur reactor permits to recover the level of the tank pH, showing that the acidity of this water is mainly due to dissolved carbon dioxide. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]h) The influence of treatments [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]The reduction of the nitrates by this way, being based on the biochemical activity of bacteria, you have to be carefull not to disrupt this activity by adding bacteriostatic or bactericidal substances like antibiotics in the tank. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]In case of reaction stopping after using it, you have to re-initiate the process by « seeding » the reactor with a small quantity of new " sulphur " and to take the procedure at step one. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]On the other hand I never noted any consequences on the reaction when using copper sulphate. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]i) Stopping the reactor [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]In case of necessity, you can stop the reactor and re-use it easily if you have maintained a sufficient population of bacteria in life. The best solution is to empty the reactor of its water and to close it to prevent sulphur from drying ; in this case the bacterian activity re-start generally very quickly when flowing then the reactor with water. However for more security it is better to check the nitrites at the reactor exit and to limit the flow rate (only if they reappear), as at the time of the first starting. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]If you maintained the reactor with water inside, stopped during a long period, it is better , either to throw water contained in it and to proceed as describes here above, or then to send this water in the tank but at a very low flow rate if you cannot make otherwise.Water having stagnated in the reactor in very reducting condition risks to contain a important quantity of sulphide. [/FONT]
    [FONT=&quot] [/FONT]
    6°) Use as limestone reactor

    [FONT=&quot] [/FONT]
    [FONT=&quot]More lately some users wished to use this type of sulphur reactors for their only ability to produce CO2 and to make a limestone reactors. The autotrophic denitratation on sulphur is able to work even with very low rates or even non detectable nitrate by the available aquariophily methods of measurement (typically lower to 0.5 mg/l) and with relatively elevated rates of oxygen contrary to the heterotrophic denitratation. You can produce an acidic water at relatively elevated flow rate (sometimes superior to 5 l/h by liter of sulphur) even when the tank nitrate rate is non-detectable ; this water can be flew on a calcareous substratum to get an important production of calcium very easily but it seems more difficult to grow the KH by this way. [/FONT]
    [FONT=&quot] [/FONT]
    [FONT=&quot]It is likely that in these level of flow rate a big part of the sulphur column works in aerobic condition and that the reactions are not anymore the same. This use can be interesting but I didn't specifically study it. [/FONT]
     
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  3. jacquesb

    jacquesb Retired Moderator

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    Cool Mo_G. I am glad that this worked for you. BUT, just our of interest sake - I have a DSB - and mine works just as well. My nitrates are ALWAYS less than 5 (and I overfeed heavily).....

    Isn't the building of a denitrator a lot of PT? I did that once too - and it took me about a week to build mine. BUT, mine never reduced my nitrates below 20.... (I used the same formula/design as this one).
     
  4. Nemos Janitor

    Nemos Janitor

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    I am also a Nitratereductor fan. IMO they work far better than a DSB. But they are expensive. So if a client cannot afford a nitratereductor then a DSB is the next best thing. I seem to get better results with a reductor and a refuge.
     
  5. Mo_G

    Mo_G Thread Starter MASA Contributor

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    The problem is if something dies or you do not have space for a DSB. I am using mine in a tank that has massive bio-load. It is however better to use a pump to circulate the water inside the chamber if its large enough.
     
  6. Mo_G

    Mo_G Thread Starter MASA Contributor

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    some images I took

    this is the test before trying sulphur using the LaMotte, I also tested with Sera which was above 50ppm
    [​IMG]
    [​IMG][​IMG]
    [​IMG]
     
    Last edited: 17 Mar 2010
  7. Mo_G

    Mo_G Thread Starter MASA Contributor

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    test from the reactor after 2 weeks nitrate 0
    [​IMG]

    test from tank after 2 weeks trace of nitrate < 0.25
    [​IMG]

    left output of the reactor is zero and on the right +-0.25ppm from the tank with Salifert
    [​IMG]
     
    Last edited: 17 Mar 2010
  8. Mo_G

    Mo_G Thread Starter MASA Contributor

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    for anyone that likes to try, there is no need to buy expensive equipment.
    I have used 2L PicknPay milk bottle. just add some tape on the thread.
    this should not take more than a hour.

    2 bottles will be required, 1 bottle for sulphur and the other for carbonate.

    I used a small pump 500lph
    the bottom is the inlet and the top, cap is the outlet
    I fitted an irrigation pipe from the inlet, running to the bottom of the bottle
    you must try to have the pipe as center as possible
    I used another elbow in the inside so that I do not need to bend the pipe
    I used a RO pipe from the pump than air tubing going to the inlet and coming out of the outlet

    [​IMG]

    [​IMG]

    please make sure that you follow a drop per second but if it smells increase the flow slightly.
    after 3 days or so test the water coming out of the reactor, once its 0, increase the flow slightly.
     
    Mekaeel likes this.
  9. Mekaeel

    Mekaeel Moderator MASA Contributor

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    Thanks for sharing Mo! I see you had time to take out these pics and share with us, now share some pics of your tank ;)
     
  10. Mo_G

    Mo_G Thread Starter MASA Contributor

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    this is a 1m reactor I build with 110mm PVC pipe which holds +-10L sulphur but had to upgrade because it could not keep up with the bio-load. The concept is the same as the milk bottle.

    [​IMG]

    [​IMG]

    some of the bio-load in my holding tank
    [​IMG]
     
  11. Mo_G

    Mo_G Thread Starter MASA Contributor

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    this is what I am using currently
    AM 5000 sulphur
    [​IMG]

    carbonate
    [​IMG]

    output
    [​IMG]

    tunze 9010, I get 400-500ml every 6-7 days and the condition of the pump is not 100%
    [​IMG]
     
  12. Redhawk10

    Redhawk10

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    hi there. i would like to know how much sulphure must i use for my tank (800L)?
     
  13. Mo_G

    Mo_G Thread Starter MASA Contributor

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    nitrate < 50ppm 1L sulphur per 100L
    nitrate > 50ppm 2L sulphur per 100L
     
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