What ppm nutrient levels should I be trying to keep?

Oreo

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May 6, 2010
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So I'm usually a bit of a black sheep with my methods of all things. Dosing my aquarium is probably no different. I'll be setting up an industrial diaphragm pump to continuously dose my macro nutrients. (I'll still be doing the iron & micros manually) This combined with my constant tap-water drip instead of doing water changes should allow me to keep a fairly constant level of nutrients in the water at all times. So assuming a standard 30ppm of CO2 in the water what should the levels be for N, P, K, & Fe?
 
C

csmith

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I've come to understand you want no less than:
N: 20-30 ppm
P: 2-3 ppm
K: 20-30 ppm
Fe: 0.5-1 ppm or higher
 

Tug

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Tom talks about it a little on this thread, for individual inhibitory concentration levels, adding more than these rates will not help further plant health. http://www.barrreport.com/showthrea...Dosing-or-No-Need-for-Test-Kits?p=217#post217

You can dose more/higher levels. That's the governing paradigm behind EI.. Better to provide luxury amounts, then limiting nutrients. Still, you did ask.:cool:
N: 10 ppm (to keep away BGA)

P: 2.5-3 ppm (NO3:pO4 = 3-4:1)
GSA will tell you if your dose of PO4 is off/low.

K: 10 ppm
(works out to be about equal to the NO3 levels)

Fe: 0.3-0.7 ppm (higher?)
Tom Barr;46079 said:
6ppm was the best as far Hydrilla, one of few aquatic plants to have Fe studies done on it.
Now, if you want to add the nutrients from things like fish food to your calculations of stuff, try Wet's calculator. http://wet.biggiantnerds.com/ei/con_v_time.pl
 
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Oreo

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Thanks guys. I don't need too much of a fancy calculator for it. I can adjust the dosing based on the levels when I test. I just needed to know what I'm aiming for. I wasn't sure if it was any different with pressurized CO2 injection compared with my old low-tech dosing guidelines.
 

Farmhand

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Tug;51455 said:
K: 10 ppm
(works out to be about equal to the NO3 levels)

So if your dosing based on testing(not EL), would you dose K the same rate as N03 assuming plants use the two the same?
 

Tug

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No

Most of the K will come from your doses of KNO3 and KH2PO4. Adding a small amount (about half the KNO3 dose) of K2SO4 is old school. A lot of people get by with out adding it. Tests! We don't need no stinking test.
 

Tom Barr

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Oreo;51462 said:
Thanks guys. I don't need too much of a fancy calculator for it. I can adjust the dosing based on the levels when I test. I just needed to know what I'm aiming for. I wasn't sure if it was any different with pressurized CO2 injection compared with my old low-tech dosing guidelines.

Well, you will use about 5-10X more nutrients than you did with the non CO2 methods..........

Ball park is fine, but please calibrate any test kit and make good measures before you alter and change anythuing based on test kit data.
Never adjust dosing based ona guess that the test kit is accurate or not.

A guess is still a guess whether you use a test kit or not.
May as well bet on lucky 7.

Regards,
Tom Barr
 

Oreo

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May 6, 2010
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LOL, I'm a professional. I ain't using no stinking test "kit". ;)

The idea is that I'll mix up my macro's in a 3gal batch. The diaphragm metering pump once an hour will inject just enough of the macro solution to keep the levels constant. I can custom tailor the macro solution to adjust for some nutrient demands being higher then others. If say, the NO3 demand is a little higher then I'll put a little more of that in the fert solution. If I notice the K residual has been increasing steadily then I'll make the next batch with a little less of that. At first I'll test about once every other day or so and make adjustments to dose size, and macro solution content. Once I get things dialed in I expect I'll have to test weekly and make periodic adjustments to the system but I'm hoping I can get it all dialed in close enough that I can leave town for a couple weeks on vacation and when I come back things are more or less as they should be in the aquarium.