Hi & Help!

mick b

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Hi Ceo,

This is the bit, I had not grasped, with regard to nitrogen in the water cloumn (where anubias and Java fern are sited)

So the scientists categorize DIN (Dissolved Inorganic Nitrogen) and DON (Dissolved Organic Nitrogen).
The DIN is easy as it is a fraction of the KNO3 (or whichever nitrate salt is dosed) but the DON is much more complicated.


With regard to the nitrogen cycle, hair-root interface, anerobic & aerobic bacterial action etc (including trials with anerobic reactors et al), I'm OK, so don't worry, I will not have bad-egg smell wafting around, substraight has now been in place approx 7 years with one major re-fit 2 years ago, when the tank leaked!

But in simplistic terms, from the plants point of view, not all nitrogen fertillisers are the same :D

My analogy is;

The nitrogen food (ion) the plant can use, is say a chocolate :twisted:

Chocolates are present in qty, but some are not wrapped at all, others are wrapped in plastic and some in the box, in the substraight, there are mechanisims at play, which can open the box, remove the plastic and hence the plant can eat the chocolate.

Plants in water column, cannot open the box, or remove the plastic wrapper, so unless they are offered un-wrapped choc's they starve.

Unfortunatly, the organics in the tank, don't like un-wrapped choc's, so wrap any uneaten choc's (consuming oxygen in the process), hence the need to dose on a regular basis.


This is why Discus keepers cringe at EI, when informed they need to add N03, it is all percieved as bad (DON & DIN both = DOC's) and our test kits do not differentiate DON from DIN.

Actually I think the accepted norm is 6 grams per teaspoon for these powders, but no matter, there is no need for super accuracy. Doing a daily change complicates things a bit. I'm more inclined to use 16 grams per week of KNO3 + 3 grams KH2PO4 but your numbers are more or less fine. Again, there is no way to predict whether you will need more or less. These are good starting values as long as you dose after the water change. Wait 3 weeks and make adjustments after observing the plants reactions.

OK, Off now to order the components, and will mix up 4 weeks supply, dose daily 1st thing (follows night time WC) and see what happens, I will report back.

Many thanks for taking the time to explain stuff, I have been trying to grasp for more than a few weeks!!!!

Cheers, Mick B 8)
 
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I think maybe in time I might give discus keeping a go, it'll take me 5 years of nagging/begging/tricking the wife into letting me setup yet another tank :lol:

Still, they do look good :D
 

mick b

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22 Jul 2008
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Hi Ceo / All,

Nearly 3 weeks into EI and there are visible signs of re-growth from both anubias and Java fern, :D
Plus increased growth from substraight rooted plants :D

A slight increase in green-spot algea, but nothing to write home about.

Water test, mid point between WC & Doseing is;
N03 15ppm
P04 4 ppm

The N03 has actually dropped, so your statement;
This may sound bizarre, but the non-CO2 method assumes that 80%-90% of the macronutrients will come from inorganic sources, but the dosing of inorganic KNO3 and KH2PO4 at low levels actually improves performance quite a bit. That's because the uptake of NPK is faster for inorganic nutrients than for organic nutrients.

Seems to be true :D

But, the increase on phosphate from 2.5ppm to 4ppm ??

Should I reduce the doseage of phosphate?? :?:

Cheers, Mick B
 

ceg4048

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Hi Mick,
The best advice I can give you is to....RUN - do not walk, away from your test kits. They will kill you because they give false readings. If you don't fully grasp the biochemistry of plant growth and then if you respond to the test kit readings you will almost always make the exact opposite decision you should make.

In fact, in your post you've just summed up the ultimate hypocrisy of test kits without realizing it: The test kit tells you that you have high Phosphates, yet you noted Green Spot Algae (GSA) which is almost always caused by low Phosphates. You can clearly see the evidence in front of you, yet you immediately contemplate lowering your PO4 dosing.

Here is a choice you must make: Do you choose to believe the test kit, or do you choose to believe the GSA?

To help you with that choice I'll show you an image I use a lot to illustrate low vs high PO4. Just as the rings of a tree trunk show the history of it's growth, this image shows a plant living under very high light and feeding from two dosing regimes - Low PO4 (probably less than 3 ppm) and High PO4 (over 9 ppm). See if you can determine which leaves lived with low PO4 and which lived with high PO4:


So should you reduce your PO4 dosage? I leave the choice to you...

Cheers,
 

mick b

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22 Jul 2008
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Hi Ceo,

No I won't throw away the test kit, just re-calibrate, what is working.
Was 2ppm, now after doesing, 4ppm and GSA which from articals is low PO4, so potentially increase dose of PO4 9but I'll maintain as-is for now).

This edit, form a link by GF in articals threw me :?:
To prevent this algae (GSA), do weekly water changes, do not overfeed nor over-stock. In planted tanks keep slow growing plants in places where they will get less light (low light set-ups should not suffer from this algae in large extents) and keep Phosphate levels between 0.3-0.5ppm and CO2 levels 30ppm.

0.3 to 0.5 Ko4 ppm

You are saying (and my tank agrees :D ) 4 to 7ppm KO4 is a working range (if I read between the lines )

See why I was hestitant :lol:

So, more of the same and I will update as things develope.

Cheers, Mick B 8)
 

mick b

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22 Jul 2008
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Hi George,

Glad to be hear :D

Have to say, this place is an absolute gold-mine! for those taking a plunge into the 'dark-side' :lol: :lol:

:?: Are you back from your travels?
(been earwigging, some scary places you seem to be visiting! and not improving, from what I hear on the TV!).

Cheers, Mick B
 
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