Estimated Ratio of NPK uptake? - The Planted Tank Forum
 
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 07-05-2005, 02:35 PM Thread Starter
Planted Tank Guru
 
PTrader: (92/100%)
Join Date: Mar 2005
Location: Phoenixville, PA
Posts: 2,026
Send a message via AIM to Jason Baliban
Estimated Ratio of NPK uptake?

Providing K to your plants seems to be a little bit of a mystery sometimes. I dont have a test kit for K, nor do i think i will be picking one up. Does anyone have an estimate on uptake for the 3 macro's?

While this estimate will be impossible to come to, it may be worth while to come up with a ratio. For example can we assume that uptake happens in a ratio of 10:1:10? (NPK) The fertilator on APC gives a target range for these macros in this ratio. Can it be assumed that the uptake is the same? Any thoughts on this?
Thanks
jB
Jason Baliban is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old 07-06-2005, 03:09 AM
Planted Tank Guru
 
plantbrain's Avatar
 
PTrader: (267/100%)
Join Date: Dec 2003
Location: The swamp
Posts: 13,609
The uptake rates vary widely over a range of parameters.
So the NO3 uptake is say 1-4ppm/day, the PO4 might be 0.1-0.4ppm per day and so on.........

But.........the plants needs also vary widely with respect to a ratio..........some plants do fine over a wide range of ratios...........

This also corresponds to the observations in our tanks as well.
Mineral assimilation and this type of topic is next month's issues on my site.
I've dug most of the references out already.

Plants are more flexible than many seem to assume and like to micromanage too closely. And I can prove that.

Regards,
Tom Barr

www.BarrReport.com



plantbrain is offline  
post #3 of 6 (permalink) Old 07-06-2005, 03:17 AM Thread Starter
Planted Tank Guru
 
PTrader: (92/100%)
Join Date: Mar 2005
Location: Phoenixville, PA
Posts: 2,026
Send a message via AIM to Jason Baliban
Thanks for jumpin in Tom!! I think it is pretty easy to see how these values and ratios will change a great deal from situation to situation. If plants were hard and fast as far as a narrow band of exceptable conditions......our forums would be bare. HEHE

Do you think for arguments sake a base ratio can be assumed? EI assumes a ratio as well. What would we consider a starting point for uptake ratio? Or am I way off here?

It seems that nobody really measures for K. It has been assumed that excess K is not a prob for a tank. However, these 3 macros are related to each other. How does one measure or assume what your weeds are using as far as K? This was the basis for my ratio.

Thanks
jB
Jason Baliban is offline  
 
post #4 of 6 (permalink) Old 07-06-2005, 02:08 PM
BSS
Guest
 
PTrader: (12/100%)
Join Date: Sep 2004
Posts: 1,600
Can't help with the ratio, but when I started noting pin holes in my older Anubia leaves, I decided I needed to add more K. I had stopped dosing K2SO4 at that time, but it's back in my schedule now.
BSS is offline  
post #5 of 6 (permalink) Old 07-06-2005, 07:59 PM
Planted Tank Guru
 
plantbrain's Avatar
 
PTrader: (267/100%)
Join Date: Dec 2003
Location: The swamp
Posts: 13,609
Well, a generalized ratio is 10:1:10-20

PO4 would be the best test kit to measure the rates with.

Regards,
Tom Barr



plantbrain is offline  
post #6 of 6 (permalink) Old 07-07-2005, 02:41 PM
Planted Tank Guru
 
Georgiadawgger's Avatar
 
PTrader: (16/100%)
Join Date: Apr 2004
Location: Alexandria, VA
Posts: 2,422
I would say that Tom is about right on an estimated uptake, based on PO4.

My tap water PO4 is about 5 (dark blue on the AP kit). My tap NO3 is around 10 so I add enough until it gets to about 15-20 ppm. This is on Sundays after water change.

On Tuesday morning I'll test PO4 before I head to work and not much of a difference, except the PO4 is a tad bit lighter...maybe down to 3ish ppm. NO3 is about 15.

By Thursday my PO4 is around 1-2 and NO3 back to 10. So that's the only other time I dose macros to push my NO3 back to 15-20 and my PO4 to 2-3.

But then again, I'm convinced this uptake is based on the types of plants I have. I do have a couple large swords, but the majority of my uptake is probably through my giant hedge of wisteria, my P. stellata stand and stargrass.

Re-boot!
Georgiadawgger is offline  
Reply

Tags
None

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome