Using EI - What if PO4 and NO3 testkits show very high?

Spar

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Jun 5, 2005
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I hadn't tested in a while for my NO3 and PO4, but yesterday it showed up as over 50ppm on NO3, and over 10ppm on PO4.

Is this a sign that I can/should cut back on dosing? I have Java Fern mostly, also some Water Sprite (not doing too well), and Red Tiger Lotus. Plenty of light.

It is a 50g (40g water) and I am currently adding 1/2t KNO3 & 1/8t KH2PO4 4x per week.

Any thoughts as to cutting back or not?
 

Wö£fëñxXx

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Jan 24, 2005
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Re: Using EI - What if PO4 and NO3 testkits show very high?

That amount of ferts 4x a week is wasteful and not needed :D

3x a week is plenty, I wrote you a regimen out already! how are the plant's? ;)
 

Tom Barr

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Re: Using EI - What if PO4 and NO3 testkits show very high?

Yes, cut way back, 3-4x or so.

Regards,
Tom Barr
 

Spar

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Jun 5, 2005
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Re: Using EI - What if PO4 and NO3 testkits show very high?

so only do 3x per week and then also cut back maybe to 1/2 of my current dose amount?

Plants are actually looking a little bad since I switched over to EI. thought it was just the beginning of a new method, but my Jungle and Corkscrew Val, Java Fern, and Water Sprite are all browning quite a bit.

I did opt to keep my lighting at 260watts though (a theoretical 5.2wpg ratio). I did this since it is a Paludarium only 1/2 full. There really is no way to "know" what the wpg is hitting the water since 15" of space is between the top and the water. 3.9wpg is the next possible amount (cut one light off of the 4 I have), which could very possibly be doing < 3wpg.

I just ordered a new Pinpoint pH Reader so I can check if I am for some reason not getting a "true" reading of pH. Maybe not enough co2? Red Algea is still busting through my tank. It appears to be co2 = 50ppm right now. Won't high PO4 cause a mis-reading though?? It is 10ppm+ right now.

edit>> any idea why my plants arent consuming as much NO3 and PO4 as others utilizing EI?
 

Tom Barr

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Re: Using EI - What if PO4 and NO3 testkits show very high?

Well, you do not need this much light nor nutrients.
More CO2.........less NO3/PO4. 3-4x less.

3.9 is plenty, ADG does not use nearly as much as you are.
Do large water changes, like 80% 2x a week to lower the levels, add Excel and more CO2.

BBA does not appear unless the CO2 is off.
Get rid of what is there, then add more CO2.
Reduce the EI dosing amounts.

Regards,
Tom Barr
 

Spar

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Jun 5, 2005
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Re: Using EI - What if PO4 and NO3 testkits show very high?

ADG (via Mike Senske) was actually who told me to stick with the 5.2wpg due to the height differential between the water and the fixture (15"). It is probably more like 4wpg by the time it reaches the water, accounting for the light lost to the sides, etc.

If that is true (which it may not be... I am merely assuming), then 3.9wpg would be less than 3wpg by chance. I can always cut back no problem though. So, if they overwhelming recommendation is to cut back on light, I will try it out.

Extra question now that you brought it up. If I am pumping 30ppm+ co2 into my water, is adding Excel still beneficial? I have several bottles of it that I have not opened and could start dosing along with co2. Maybe even just a 1/2 dose. Any thoughts?

My new dosing strategy and stats with reduced EI rec's in my 50g is:
KNO3 - 3x/wk @ 1/4t/ea
KH2PO4 - 3x/wk @ 1/16t/ea
K2SO4 - 3x/wk @ 1/8t/ea
Traces - 3x/wk @ 10ml (CSM+B 75% and Flourish 25%)
Mg - 1x/wk after WC - 1/2t
Excel - 1-2x/wk - 1/2 dose
Lighting - 195w (3.9wpg) for 11/hrs/day
co2 - hopefully 40ppm

Sound about right?