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what are the target ranges, in ppm for plant ferts? for K, iron, etc... :oops:
 

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I think most will have their own optimized levels, here's what I have found to work well in my 55gal high light tank:

Water:
- FE <=0.2ppm
- K 5ppm dosed after water change and another 5ppm distributed daily throughout the week (I don't have K test kit) (K2SO4)
- NO3 5ppm (KNO3)
- PO4 0.2-0.5ppm (Fleet Enema)
- CO2 20-30ppm
- Flourish 10ml after water change, 10ml distributed daily throughout the week
- CSM+B 10ml distributed daily throughout the week

Substrate:
- 10-12 Flourish tabs approx every 2 months

Regards
Giancarlo Podio
 

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First you need to get some chemicals. Go to Greg Watson's web site at
http://www.gregwatson.com/
Order 2 pounds of CSM+B. Plantex CSM is a trace element mix that also contains iron. Greg puts some Boron in it and calls it CSM+B
Order 2 pounds of potassium nitrate and one pound of monopotassium phosphate.

Tom Barr is the guru on adding nutrients. He will probably say to add:
1 to 2 ppm KH2po4 twice per week
10 ppm KNO3 twice per week
and between .1 and 2 ppm Fe.

For phosphate:
In general to get 1 ppm PO4 from KH2PO4 use 53.9 mg per 10 gallons. For 150 gallons thats .8 grams (twice per week)

For Nitrates
To get 10 ppm NO3 from KNO3 in each 10 gallons of water add .62 grams of KNO3. So for 150 gallons add 9.3 grams KNO3 twice per week

For Fe and traces.

First mix a concentrated solution of 47.8 grams of CSM+B to make 250 ml of water.

.6 ml of concentrated solution to make .2 ppm Fe in 10 gals
6 ml of concentrated solution to make .2 ppm Fe in 100 gals
30 ml of concentrated solution to make 1 ppm Fe in 100 gals
45 ml of concentrated solution to make 1 ppm Fe in 150 gals
22.5 ml of concentrated solution to make .5 ppm Fe in 150 gals

I would go with the 22.5 ml to make .5 ppm Fe (twice per week)

Once per week before you add the chemicals do a 50 % water change to reset the nutrient levels.
The above is all you need to know about nutrients.

The Ca and Mg and KH and GH is another issue.

This is probably for 3.5 Watt/gallon and less. Otherwise all bets are off. Reduce the lighting.

email me if you have any other questions

Steve Pituch
 

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jdigiorgio said:
what are the target ranges, in ppm for plant ferts? for K, iron, etc... :oops:
From Thomas Barr et al's (as Tom insists :wink:) "The Estimative Index", the target ranges are as follow:

CO2: 20-30 ppm
NO3: 5-10 ppm
K+: 20-30 ppm [This is a debatable range. However, it has been recently somewhat agreed upon that additional K dosage is unnecessary if your nitrogen source is KNO3.]
PO4: .4-1.0 ppm
Fe: .5 ppm or higher (?)

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Recently, the NPK ratio of 10:1:10 has gained popularity. Note that's NITROGEN not NITRATE (NO3) & PHOSPHORUS not PHOSPHATE (PO4) that are represented in the ratio. This should merely be used as guidelines because some nutrients, particularly phosphorus and iron, form insoluble compounds that plants cannot utilize.

Chuck Gadd's Planted Aquarium Calculator (downloadable Windows applet) is a great tool to figure out how much to dose. Or ask Steve Pituch, our resident mathematician. :p

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The KH and GH (Ca/Mg) should be >= 3 degree. 1 degree = 17.9 ppm CaCO3

George Booth's "Tech Brief: Water Chemistry"
 

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cS said:
Recently, the NPK ratio of 10:1:10 has gained popularity. Note that's NITROGEN not NITRATE (NO3) & PHOSPHORUS not PHOSPHATE (PO4) that are represented in the ratio
Just to f/u on above formula, some calculations done by Ghazanfar.

Using KNO3 and KH2PO4 to acheive a 10:1:10 ratio..

N : P 10:1 ratio

NO3 : PO4 ratio
5 ppm NO3 (1.14 ppm N) : 0.35 PO4 (0.114 ppm P)

If you're using KNO3 as your primary source of N, for 1.14 ppm of N - you're already adding in 3.15 ppm of K. So K is already in excess if
using KNO3 as Nitrogen source.
 
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