One day before water change and this is my N P K analysis

Gbark

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Jun 15, 2009
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Hi All,

I have had my water tested by my chemist friend in the lab.

Water change due tomorrow,

N = 25ppm as N
P = 25ppm as P205
K = 80ppm as K2O

Is this ok?
 

Wet

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The elements we care about are high when brought to our normal (NO3, PO4) states, but one of the best things about EI models is water changes provide gradual (fish) and effective change. Are those measurements without or with dosing anything to the tank between the last water change? If dosing, how much of what between how long of water changes? How long have you been doing it that way? This will be fun to look at if you have all this info.
 

Biollante

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High Even By (My Lack Of) Standards

Gbark;47971 said:
Hi All,

I have had my water tested by my chemist friend in the lab.

Water change due tomorrow,

N = 25ppm as N
P = 25ppm as P205
K = 80ppm as K2O

Is this ok?

Hi,

That is high.

What are you dosing and are there plants?

NO3 of 110-ppm
P of 35-ppm
K of 22-ppm

What Wet said.

Biollante
 

Gbark

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Wet;47982 said:
Are those measurements without or with dosing anything to the tank between the last water change? If dosing, how much of what between how long of water changes?

With dosing weekly water changes.

125ltr tank
50ltr water change weekly

Dosing Daily

KNO3 3.5ppm
KH2SO4 1.7ppm
MgSO4 2.1ppm

TPN 3ml

Wet;47982 said:
How long have you been doing it that way?

Sep'2009
 

Gbark

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Biollante;47987 said:
Hi,

That is high.

What are you dosing and are there plants?

There are plants, it was very heavily planted up to beging last week, and i have had a clear out, got rid of a red special and pruned heavily

Maybe i should increase the water changes.

I was also thinking of pulling my dosing inline with the EI for my tank

Kno3 = 4.86ppm ( maybe not such a good idea now looking at my NO3 level)
KH2PO4 = 1.2ppm
MgSO4 = 1ppm
 
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Gbark

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Biollante;47992 said:
Hi,

I seem to recall you had a tap water analysis, could you re-post that?

Biollante

I don't sorry, i use RO water. :D

Im so MAD with myself i could swear!!!!!!!
I thought i had this EI stuff sorted.
 
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Biollante

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Whoa, Up Pilgrim!

Hi,

Whoa, up pilgrim!

Do you have a cat pooping in your aquarium? :confused:

The nutrients are coming from somewhere. :)

How sure are you of the amounts you are dosing your tanks? This is where stock solutions and every other day dosing come in handy for the smaller under 200-gallons tanks. :)

Seeing those lab results says something is going on. Are all the fish accounted for? Are there any off smells?

Regardless, I think you need a very large, like 70% water change. :cool:

Do not worry we will get it sorted out, actually I think a good lab analysis would be helpful for a lot of folks, I know it helped me. :)

Good luck,
Biollante
 

hani

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Gbark, i had the same problem, it usualy happen after 4-5 month, did all my testing with lamotte colormeter, i doesed half the required does of the EI (50% of the recomende amount), my po4 still goes up to 4-5ppm, the kno3 went down from 35-40ppm to 20-25 ppm.
i notice no diffrence in plants growth with both values, this is my 3rd tank,
it seems the intake is high the first few weeks, (i kept dosing EI and testing befroe wc), the plants seems to concume most of it. When the tank mature, the requrment seems to go down specially with fish and food, the EI seems to be very rich at that point, still works though..
If your using AS, your # will be high.
am not an expert, but theese are my notes
 

nipat

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May 23, 2009
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The amount you've been dosing (4.86 PPM)
will result no more than 4.86x7x2 = 68 PPM long term,
given no plant uptake at all. But your NO3 level is around 110.
That must be from somewhere else.

I remember Tom said he dosed about 1/3 to 1/2 EI when using
Aqua Soil or other rich sediment.

Ah, found one: http://www.fishforums.net/index.php?showtopic=231742
 
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nipat

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If you decide to reduce KNO3 (and KH2PO4), you may have to add K2SO4 to keep K level.
 

Philosophos

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I reconfigured things a little so they're easier for me to look at. If you're not big on math, ignore the number beside the quantity.


Tested:
NO3: 111ppm (25*62.00501/14.00672)
PO4: 33ppm (25*(61.9475244/141.9446744)*(94.9714822/30.9737622)
K+: 66ppm (80*78.19662/94.19605)


Dosed:

NO3: 21ppm (4.86*7)*62.00501/101.10332
PO4: 6ppm (1.2*7)*94.9714822/136.0856722
K: 16ppm (see math on next line)

K=(1.2*7)*39.09831/136.0856722+(4.86*7)*39.09831/101.10332

Now here's the interesting bit; divide the NO3 tested by the NO3 dosed. Do the same for the PO4 and the K+. Here are the results I got from the spreadsheet I made:

NO3: 5.3
PO4: 5.71
K+: 4.27

So there's almost identically 5.5x more NO3 and PO4 as should be there. K+ is tricky stuff to measure and the column isn't very accurate, so a lower number isn't too out of line. The fact that it isn't present in fish food could account for some of it as it as well.

Because of all this, I think it's worth looking into dosing methods. How many grams/ml/teaspoons are you dosing of these compounds each day? If it's as a stock solution, could you give the quantities that you're adding for each batch?

My numbers aren't a definite indicator of dosing as an issue, but K+ doesn't pop up at those concentrations in a tank that easily. The only other way I see even being a possibility is if you have a substrate that you've enriched with K2SO4. The NPK ratios seem off for ADA AS, and it's 7 months old.
 
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Gbark

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Jun 15, 2009
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Biollante;47995 said:
Hi,

Whoa, up pilgrim!

Do you have a cat pooping in your aquarium? :confused:

The nutrients are coming from somewhere. :)

How sure are you of the amounts you are dosing your tanks? This is where stock solutions and every other day dosing come in handy for the smaller under 200-gallons tanks. :)

Seeing those lab results says something is going on. Are all the fish accounted for? Are there any off smells?

Regardless, I think you need a very large, like 70% water change. :cool:

Do not worry we will get it sorted out, actually I think a good lab analysis would be helpful for a lot of folks, I know it helped me. :)

Good luck,
Biollante

I 've never caught my Cat pooping in the tank LOL! she would have a job getting up there.

I have done a 50ltr water change and cleaned my filter and pumps, found a dead sucked up fish in one of my pumps, Could explain something!

Waiting for the next batch of 50ltr RO water to do another

I made my own stock solutions i add daily

3.5ml KNO3 (102g to 500ml RO water) bit of a under dose for my tank size i think
3.5ml KH2PO4 (46g to 500ml RO water)
14ml MgSO4 (95g to 500ml RO water) Too much for my tank i am lead to believe
3ml TPN
 
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Philosophos

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Off your tank I'd presume about a 100L column if 125 is total capacity.

That being said, your dosing based on the stock solutions would actually end up being:

NO3: 30.65ppm
PO4: 15.73ppm
K+: 25.8ppm

The K+ isn't too far off the max of EI. The PO4 isn't far out of line either. Both of these could be a matter of an inaccurate scale, a measuring cup marked wrong, a few extra ml's dosed, etc. coupled with low light and/or limiting CO2. It may be one thing, it may be many; try testing your stock solutions, scale and measures perhaps. Once you're sure these are accurate, you can always check to see if your substrate is leeching in a big way using hobby test kits. I'd call the levels pretty high, but not impossible.

The NO3 is very far out of line from the rest of the excess though. A Dead fish in the filter, or even an unclean filter might help to explain this.
 

Tom Barr

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Gbark;47989 said:
With dosing weekly water changes.

125ltr tank
50ltr water change weekly

Dosing Daily

KNO3 3.5ppm
KH2SO4 1.7ppm
MgSO4 2.1ppm

TPN 3ml



Sep'2009

Max possible levels minus fish food for 50% water change and tap water that's 0ppm.
49ppm as NO3
I assume that's KH2PO4: 22ppm as PO4

You can also do a larger than 50% or more frequent.

Regards,
Tom Barr

:
 

Gbark

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So to re-cap

My dosing daily dosing amounts ok!

But as my NO3 was way above, the dead fish and dirty filter could be the cause.
 

Tom Barr

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Spend time and effort, $ cleaning tank, filters, doing good water changes etc, less on test.

Works for most.

Regards,
Tom Barr
 

Wet

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I was all excited to use this calculator to build a model for you and how to drop it, but it was better explained here anyway. But an informative toy you could play with using your current numbers and how water changes will fix it: http://wet.biggiantnerds.com/ei/con_v_time.pl

Also wouldn't be surprised by the numbers if there were any substrate ferts and/or no series of water changes after that recent uprooting of several month's worth of plants.
 

Gbark

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Jun 15, 2009
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Wet;48041 said:
I was all excited to use this calculator to build a model for you and how to drop it, but it was better explained here anyway. But an informative toy you could play with using your current numbers and how water changes will fix it: http://wet.biggiantnerds.com/ei/con_v_time.pl

Also wouldn't be surprised by the numbers if there were any substrate ferts and/or no series of water changes after that recent uprooting of several month's worth of plants.

That is handy, :) Does account for plant up take though?