Nitrate Level Very High

Discussion in 'Aquarium Fert Dosing' started by phantomfisher, 27 Dec 2009.

  1. phantomfisher

    phantomfisher Member

    Messages:
    56
    I am struggling to control the Nitrate level in my planted tank.

    I have 25 small fish in the tank mainly Barbs, Tetras and a few Oto’s and am aiming to keep the Nitrate level at around 50 or below if possible however I have never managed to achieve this since starting up the tank about 5 months ago. I use a Nutrafin Nitrate test kit (liquid type) to test the level but it always reads at the maximum colour shade which equates to 110 so it could be even higher than this!

    All my other water readings ph, phosphate, ammonia, nitrite etc are good and I use Co2 injection for the plants and the drop checker is a permanent lime green so I think all is ok there.

    I change 50% of my tank water every week and vacuum debris from the gravel at the same time. My replacement water is Nitrate free. My fert dosing regime is:

    Aqua Essentials Trace Mix Plus

    15ml x 3 times per week

    James Planted Tank Macro Solution

    (Potassium Nitrate / Potassium Phosphate mix)
    35ml x 3 times per week

    Iron Sulphate

    35ml x once per week

    The plants all appear to be growing well the only notable issue is that a number of the Echinodorus Bleheri leaves have black edges and the veins are quite pronounced.

    My main concern in all of this are the fish which do seem nice and healthy even with the high Nitrate. I had hoped that the plants would use the Nitrate and keep the level low but this does not appear to be happening. Could it be that the Potassium Nitrate is helping to keep the Nitrate level high?

    As always all advice is much appreciated.
     
  2. Dolly Sprint 16v

    Dolly Sprint 16v Member

    Messages:
    1,611
    Location:
    Cheshire
    If your Nitrates are high, your Nitrites / Ammonia are high as well - these running in parallel with one another - so if you Nitrates are low everything else is low. I would start doing 25% water changes every day and stop adding in any (Potassium Nitrate / Potassium Phosphate mix) for at least a week. Personnel I think you have been adding more of (Potassium Nitrate / Potassium Phosphate mix) than the plants are consuming thus you have ended up with high Nitrate levels.

    Regards
    Paul.
     
  3. Dave Spencer

    Dave Spencer Member

    Messages:
    1,389
    Location:
    N. Wales
    If you are to believe your test kit, then you need to ask yourself if any harm is being done. With nitrates up at around 100ppm, then you are possibly dosing too much (I haven`t checked your dosing figures...too lazy :rolleyes: ). With low nitrate tap water, water changes should bring the levels down. If not, then I would suspect your test kit.

    Why are you aiming for 50ppm? It seems an arbitrary figure to me.

    I don`t see how having levels of nitrate automatically equate to high ammonia and nitrite too. It is possible to overdose or have high nitrates in the tap water, none of which concerns ammonia and nitrite levels in the tank. If you had ammonia and nitite levels resulting in nitrates in the 100ppm range, your fish would have let you know by now. Don`t aim for some arbitrary nitarte figure, aim for healthy fish...which is what seems to be the case here.

    Dave.
     
  4. phantomfisher

    phantomfisher Member

    Messages:
    56
    I have checked my Nitrite and Ammonia levels and they are both 0 and as mentioned previously the fish seem in excellent health are in good colour and eating like Piranha. I have always had a problem with my tap water as it has a high background Nitrite level of 50 so I use a mix of 75% Reverse Osmosis water which I make myself and 25% tap water which gives a nice mix and a Nitrate level of around 10. I have been aiming for a maximum Nitrate level of 50 in my tank simply because this is apparently the maximum comfortable tolerance for most fish according to the numerous bits of literature and web forums I have consulted, it even says this on the test kit I have been using.

    Before I started my fert dosing regime my plants were not doing to great but since using the James Planted Tank Macro Mix there has been a noticeable improvement in growth. I use the Estimative Index system which if I am understanding the process correctly should dilute any excess chemicals (Nitrates) when the weekly 50% water change is done. The Nitrate level does drop a bit after the water change but then climes back up very quickly again.

    I am not very confident with the fert dosing method yet and I am a bit concerned about deviating from the James Planted Tank formula. Trying to keep the balance of health between fish and fauna is not easy, in one hand I am keen to sort the Nitrate issue for my fish but on the other hand want to maintain the good growing conditions for my plants. If you think I could be dosing too much, can you recommend what sort of reduction may be necessary? :?
     
  5. phantomfisher

    phantomfisher Member

    Messages:
    56
    The Nitrite and Ammonia levels are 0. I think you are probably right re overdosing on the Macro mix I use, and the 25% water changes are no problem to do, my only reservation is the daily disturbance to the tank pumping water in and out and how this might effect the fish.

    It would also be easy enough to stop the fert dosing, it is just that I am worried that the lack of both chemicals could cause plant growth to suffer and what about the trace elements and Iron, would you stop these as well? :?
     
  6. chris1004

    chris1004 Member

    Messages:
    565
    What you should really be concerned about if you suddenly stop dosing the ferts is inducing an algal bloom.

    If your plants and your fish are all healthy then your not far off doing it right so don't panic and make a load of changes for changes sake.

    Your test kit cannot be relied upon as can't any nitrate home test kit. That is probably your problem, your putting to much faith in the test results when it is well known that home nitrate test kits are at best unreliable. You could send your sample away to a lab for acurate analysis this is the only way to be sure of your readings.

    Think logically about your water for a minute. If your mixing ro-tap at a ratio of 3-1 and the tapwater is 50ppm nitrate, (again measured with a home test kit, yuk! You could get a local waterboard water analysis for your area to be more certain) then you are introducing 12.5ppm nitrate per week via your 50% water change. If you are following the correct dosing for EI as per James's instructions then you are adding about a further 20ppm per week nitrate via kno3 (pottasium nitrate). Thats a total of about 32.5ppm per week that you are introducing to your tank and if you understand EI dosing correctly then the highest possible figure that you can end up with after week 6 (and thereafter) of doing your 50% water changes is double that what you are putting in and thats assuming that none of the nitrate is being utilised by the plants. Therefore its highly unlikely unless your tanks inhabitants are producing an awfull lot of organic waste AND your plants aren't feeding that your nitrate could possibly be in excess of 110ppm, in fact I seriously doubt that its even in excess of 40ppm if you've got your EI dosing figures correct.

    Regards, Chris.
     
  7. dw1305

    dw1305 Expert

    Messages:
    8,267
    Location:
    nr Bath
    Hi all,
    If you are worried about the nitrate levels and you want to reduce the amount of nitrate you are adding, but leave everything else the same, you can substitute potassium sulphate for some of the potassium nitrate addition, adding potassium but not nitrogen.

    The problem comes from the difficulty of measuring the amount of nitrate you really have, horticulturally the normal way is to measure both the degree of "greeness" of the plant (ideally using the RHS colour chart, but a paint colour chart will do) and the growth rate of the plant. When the plant rate slows and the greeness of the new leaves declines, plant growth is nitrogen limited. The next problem comes from the difference in the optimal "greeness" and growth rate between differing plants. Horticulturally there are index figures for plants like Tomato, but in this case you would have to estimate the colour now for each plant (using the colour chart), and measure the rate of new leaf production over a 20 day period, then reduce the nitrate input and carry on estimating both colour and growth rate, until the colour becomes less green and or leaf production slackens. It is at about this level of input (because we can't accurately measure the nitrate in the tank water we won't know what this is in the tank) that nitrogen becomes limiting, so we would aim to slowly increase the nitrate levels to achieve the level of greeness and growth rate we started with.

    This difficulty was why EI, "James all in one" TPN+ were developed, for most plants they add about the right amount of each nutrient, and the large water change "resets" the datum every week, and stops things getting to out of balance.

    In my case I practice nutrient reduction, and I'm aiming for a low level of NPK in the tank water, so realistically either N or K will be limited, and I know if I add KNO3 I'll get an almost instant response of increased growth rate and greeness.

    cheers Darrel
     
  8. chris1004

    chris1004 Member

    Messages:
    565
    Hi, dw1305 / phantomfisher / all,

    I read and reread your last post with great interest a couple of times. I think I understand in principle what you are trying to achieve (in theory if not in practice) but I'm not really sure why you would want to tackle the problem of keeping nitrates as low as possible in this way.

    I know a lot of us on this forum are blinkered into thinking that EI is king but there is no denying that when its done properly it does work. The whole ethos of EI is to give the plants unlimited NPK, trace elements and co2 (without harming the fish) and use the easiest controlled factor i.e. light to limit the plants growth rate.

    It seems to me that your heading towards PMDD dosing by trying to control the plant growth by limiting the ferts, its certainly another method that works and may (?) allow the user to run his/her tank with lower nitrate values but is it really necessary? Its certainly a lot more complicated.

    Fact is we know that by week 6 (and thereafter) of the water changing regime the worst case scenario is double that of the weekly dose so by using 100% remineralised ro water and dosing 20ppm nitrate a week, which is the figure arrived at as the maximum plant uptake per week by Tom Barr after many controlled experiments, we cannot possibly have more than 40ppm nitrate in our tank/s at the end of the week (unless of course you have zero plant uptake and high organic waste production, but thats just good tank husbandry to know if thats the case or not). If the tank is heavily planted (i.e. high fert uptake), lightly stocked (i.e. low nitrate production) and well maintained (i.e. kept clean, dead leaves removed. etc.) you may well find yourself having near 0 nitrates by the time its due for each weekly water change as the ferts that were introduced were used up as they are supposed to be by the plants.

    I don't even worry about my nitrate levels anymore, don't know what they are and I don't care. Haven't tested for nitrate in nearly a year since coming on this forum and being shown the way. I know that by running my planted tank in the above manner I cannot possibly fail due to nitrate poisoning. Its impossible, as long as my plants are growing and my tanks kept clean, and if you knew me well or have followed some of my posts you would realise just how paranoid I can be over my fish at times.

    What level is a dangerous level to fish anyway? Thats an entirely different issue. Some quaters say anything above 40ppm is bad, others lower and others don't worry if its tripple that number or more. Its certainly species dependant, thats all I can really say on the subject except that I want to keep them as low as possible without starving the plants.

    The EI dosing regime allows me the freedom to control Nitrate through logical thinking and simple easy to do practical steps, and lives up to its promise of "water testing kits not required". My advice to you is to trust in EI throw away your nitrate test kit sit back and relax. If anything is seriously wrong your fish and plants they will tell you through there behavoir / growth / colour.

    Remember that observation is the true king no matter what dosing regime you employ.

    Regards, Chris.
     
  9. CeeJay

    CeeJay Member

    Messages:
    945
    Location:
    Surrey UK
    Hi Chris1004
    I have read, with interest, all of Darrel's (dw1305) posts round here and I think you'll find that his goals are somewhat different from ours that use the full blown EI method.
    Whilst I agree that EI is a simple method with excellent results, it doesn't suit everybody (and this is from a bloke who couldn't grow plants to save his life 12 months ago :lol: ).
    We must just remember that everyone's goals are different. Me, I just wanna grow healthy plants and not grow algae which I am doing with success now :D .
    Like yourself, I now just make sure I have some excess Nitrate and don't worry about it any more :lol: .
    Ultimately it is all down to the amount of time you are prepared to spend on your tanks.
    I couldn't agree more :D .
     
  10. wearsbunnyslippers

    wearsbunnyslippers Member

    Messages:
    305
    you could try mixing up a known nitrate ppm solution and then test that with your test kit to see if it is accurate...
     
  11. Behold

    Behold Member

    Messages:
    219
    Location:
    Basingstoke. Hants
    I gave up monitoring NitrAte a long time ago. My test kit used to show 80ppm in my tap water and about 100ppm in my tank. Now days it is sitting at about 60ppm and goes up on a water change. The kit is not easy to read so as long as its not going up and up on the kit i know its stable and that is what i care more about. Fish will adapt to an extent to the water conditions. I find no issues with my fish with my water. I just have to condition new fish slower than normal.
     
  12. dw1305

    dw1305 Expert

    Messages:
    8,267
    Location:
    nr Bath
    Hi all,
    Now this is a good idea, and assuming your kit is accurate, or even consistently wrong, it would allow you to estimate your tank nitrate readings, but again only at the time you tested.

    I do agree that EI does away with the need for testing. Personally I practise nutrient depletion, because in my opinion it gives you long term stability, and that is what I'm after. I don't want optimal plant growth, I want a severely macro-nutrient limited planted tank with biofilm, some DOC and water with low conductivity. In some ways the plants are there because of their positive effects on water quality, and if I wasn't interested in plants, I'd probably just grow a very limited range that fulfill my requirements.

    To give an analogy the EI approach is trying to grow "tomatoes" for maximal yield, whist I can't grow tomatoes using my approach, but I can grow Bromeliads, Orchids, mosses and ferns, most of which will show increased growth rates with increased nutrient addition, but a much lower response than the tomatoes, but some of which will be damaged by even low "normal levels" of nutrients.

    If people want an example of this look at the effect of phosphorus on the Proteas, Banksias and Myrtles from the severely P limited soils of W. Australia, they come from very low phosphorus environments, and are extremely effective at scavenging (via their mycorrhizae) phosphorus. Place them in a situation of plenty and they luxury absorb P until it kills them. I keep fish mainly from very nutrient poor waters and that is what I try to give them in captivity.

    cheers Darrel
     
  13. chris1004

    chris1004 Member

    Messages:
    565

    Hi,

    From the little I understand about acurate testing of Nitrates I don't think its as simple as that. If you were to add a known amount of nitrate to ro water then this i'm sure would give you a good idea of how things are with regard to your test kit. But as I understand it many other minerals can skew test results of home test kits and there is a margin of human error involved with the colour matching. RO+nitrate would almost be like a calibration solution but it still doesn't give you any idea wether the readings from the tank are acurate or not because you simply don't know whats in the tank water in the way of salts, minerals, gases, organic compounds, redox, TDS, conductivity etc. etc. Some or all of which may be able to falsify the results. So testing against a known solution doesn't really prove anything one way or the other as far as home test kits are concerned, (I think (?), (wheres Clive when you need him?) ).




    Hi Chris (ceejay),

    I'm really interested in what Darrel (dw1305) is trying to achieve and how he intends to achieve it but have based my previous answers mostly with referance to the OP by 'phantomfisher' who is using EI dosing and having trouble with Nitrates, (wether percieved or real).

    Oh and thanks for changing your forum name by the way (formerly chrisr01) perhaps it won't be so confusing for others now although I never had a problem with it in the first place mostly I suppose because I know which posts were mine anyhow. ;) :)


    Regards, Chris.
     
  14. CeeJay

    CeeJay Member

    Messages:
    945
    Location:
    Surrey UK
    Hi chris1004
    Like yourself, I can't see the point in stressing about Nitrates. If you have too much, the plants say yummy, if you have too little the plants complain.
    I have just checked my water report (Thames water) and the mean reading for NO3 for the year was 24.8 mg/l and I'm sticking 20 ppm in myself :oops:
    If we could guarantee the stability of their readings then I wouldn't need to bother :lol: but as the principles of EI are for unlimited nutrient availability, I put it in anyway then at least I'm sure it's in there and to date have had no problems with plants or livestock (shrimps included), so one less thing to worry about :D.
    No problem. When I checked the list of registered members there were 17 Chris's of one sort or another.
    Now that could have got confusing if they all posted in the same topic :lol:
     
  15. dw1305

    dw1305 Expert

    Messages:
    8,267
    Location:
    nr Bath
    Largely true, I think that the other factors you mention will effect the nitrate reading to some degree, and that even a perfectly calibrated test will give you no more than a fairly broad "ball-park" figure. I've mucked about for a long time with ion selective nitrate and ammonia probes, and even they are for all practical purposes useless, (unless you have a lot of ammonia present). The same also applies for potting composts, which is why growth trials are still used to test new potting compost formulations (see my other post in this thread).

    This sort of problem is why the Environment Agency use B.O.D. (Biochemical Oxygen Demand) and biotic indices to assess the health of streams and rivers. If people are interested in this sort of thing have a look at http://www.cies.staffs.ac.uk/rbms/rbms.htm, it's a bit out of date now but the program (freeware) allows you to look up a river or stream, and have a look at the biotic index based on its sampled invertebrates, and a predicted score based on the tested water chemistry and substrate. If you have a low index score, but good water quality when you tested, you have a good indication that there is/has been some form of pollution incident (we had a case locally where the Beaufort Hunt treated their hounds with a pyrethroid insecticide, and then washed them in the local trout stream, with predictable and long lasting results).

    cheers Darrel
     
  16. aaronnorth

    aaronnorth Member

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    3,955
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    worksop, nottinghamshire
  17. chris1004

    chris1004 Member

    Messages:
    565
    Hi Aaron,

    Cheers for that link mate great little read on the subject.

    Regards, Chris.
     
  18. chris1004

    chris1004 Member

    Messages:
    565
    There you go mate you already know infinatly more than I about Nitrates. Never even heard of an ion selective probe before are you sure that its not what DR Who uses to open his tardice? :) :)

    Regards, Chris.
     
  19. dw1305

    dw1305 Expert

    Messages:
    8,267
    Location:
    nr Bath
  20. chris1004

    chris1004 Member

    Messages:
    565
    Hi Darrel,

    I had a look at both of the previous links and found them fascinating, if more than a little over my head, but it begs the question why they are "for all practical purposes useless"?

    Regards, Chris.
     

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