how important is CEC cap substrate? - The Planted Tank Forum
 
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 07-08-2015, 03:01 PM Thread Starter
Planted Member
 
MJB13's Avatar
 
PTrader: (0/0%)
Join Date: Jun 2015
Location: Shiremanstown, PA
Posts: 161
how important is CEC cap substrate?

I was looking at a dirted MGOPME with a bit of turface mixed in with either Eco Complete (high CEC) or black diamond blasting sand (no CEC) for a cap. The tank will be planted and stocked with fish/inverts and (eventually) be high light and Co2 equipped.

Irregardless of appearance, which one, and why?

40 breeder - 1.25" Dirt/1.25" Black Diamond cap - Pressurized CO2 (2.25bps) - 2x54watt T5HO and 42watt LED (total 150watts; 14,500 lumens) - EI dosing - 50% weekly WC - H.O.T. Magnum 250 canister - SunSun 530 gph pump - Set-up 7-14-2015 - Cycled 8-1-2015

"Whatever is inconsistent with the facts,
no matter of how fond of it we are,
MUST be discarded or revised." - Carl Sagan

Last edited by MJB13; 07-08-2015 at 03:21 PM. Reason: BrainFart - forgot to add tank specs
MJB13 is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old 07-08-2015, 04:21 PM
Planted Tank Guru
 
Raymond S.'s Avatar
 
PTrader: (6/100%)
Join Date: Dec 2012
Location: Hot Springs Ar. 71901
Posts: 5,935
Dirt will eventually loose it's nutrients.
If you do not intend to replace it then, but rather use root tabs/capsules, then the CEC
would serve a purpose.
Dirt supplemented/w water column ferts likely will last longer. I can see a CEC sub having purpose there also.

The shortest distance between any two points is a straight line...in the opposite direction...
Raymond S. is offline  
post #3 of 6 (permalink) Old 07-08-2015, 06:35 PM
Algae Grower
 
PTrader: (0/0%)
Join Date: Dec 2013
Location: Indianapolis
Posts: 61
From what I understand, Eco is inert and doesn't have any exchange capacity whatsoever. Since it's so porous it can hold nutrients mechanically, but there's nothing chemical going on. Besides, the exchange capacity of dirt is much higher than that of manufactured substrates, to the point where I'd think the exchange capacity of the cap becomes negligible. Also, when the nutrients in the dirt begin to run out, it doesn't become useless. You can re-charge it by using root tabs or dosing liquid ferts. The nutrients from those things will find their way back into the soil.

I would mix the eco and the sand if I were you. I like the variable particle size of the eco because it looks more natural, but it's pretty light and it can be difficult to get some plants to root in it without added sand.
jacobsears is offline  
 
post #4 of 6 (permalink) Old 07-08-2015, 06:38 PM
Planted Tank Guru
 
philipraposo1982's Avatar
 
PTrader: (0/0%)
Join Date: Mar 2014
Location: Ontario, Canada
Posts: 3,020
Cec is overrated IMO. All substrates with lose their nutritional value over time. Since diy tabs are so cheap to make there is no reason to worry about high cec substrates.

75 Gallon Low Tech w/ Green Terror Pair
philipraposo1982 is offline  
post #5 of 6 (permalink) Old 07-08-2015, 06:56 PM
Algae Grower
 
PTrader: (0/0%)
Join Date: Dec 2013
Location: Indianapolis
Posts: 61
Quote:
Originally Posted by philipraposo1982 View Post
Cec is overrated IMO. All substrates with lose their nutritional value over time. Since diy tabs are so cheap to make there is no reason to worry about high cec substrates.
CEC doesn't really have anything to do with how much nutrients the substrate has, but how it holds them. Substrates with a high CEC will bind up nutrients in such a way that they're only available to the plant's roots and can't be leached out into the water column.
jacobsears is offline  
post #6 of 6 (permalink) Old 07-09-2015, 01:58 AM
Planted Tank Guru
 
PTrader: (84/100%)
Join Date: Dec 2005
Location: Sacramento, CA
Posts: 21,015
According to Diana Walstad, a dirt substrate, capped with almost any inert substrate, will still supply plenty of nutrients for several years, if you use low light. If you use high light you will probably need to be dosing the water from the beginning. Not all of the nutrients can come from the substrate if you need them at the rate that high light tanks use them. I believe potassium will be in very short supply, for example.

Hoppy
Hoppy 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