EI fertilizing for tank volume or water volume? - The Planted Tank Forum
Old 05-31-2015, 03:47 PM Thread Starter
Planted Tank Enthusiast

Join Date: Jan 2015
Location: Carmel, Indiana
Posts: 601
EI fertilizing for tank volume or water volume?

Because of the 50% water changes, it likely is a moot point. However, I was wondering how you all decide what doses to use in your tanks.

For instance, in my 75g tank. I have 200# of substrate which equates to about 15 gallons of water volume. I will be adding in hardscape (likely some boulders). So in my case it is possible that I may have only 50 gallons of water in my 75 gallon tank.

The dosing amount are quite different for a 50 gallon vs 75 gallon.

Currently I dose for tank size and have no issues with nutrient overload (as far as I can tell).

So, what do you all do?

Ben
benealing is offline

Old 06-01-2015, 02:14 PM
Planted Tank Obsessed

Join Date: Jan 2015
Posts: 385
If you were accurate, you would calculate using the actual amount of water. This would lead to the expected ppm for each nutrient.

In your example, if you dose for 75g and actually have 50g, you are dosing about 50% more than you think (in terms of ppm).

But the ppm ranges are so wide (i.e. 15-30ppm) that it probably doesn't matter (unless you target the high side).
imcmaster is offline
Old 06-01-2015, 02:38 PM
Planted Tank Guru

Join Date: Dec 2012
Location: Hot Springs Ar. 71901
Posts: 5,934
Additional thought...how might you guess correctly ?
I understand the problem/w guessing how much water you removed from the supposed total when you put in the sub etc.
So I enter 8.5g when I use the calculator instead of the 10g tank size.
Once you have all the "stuff" in there take out some of the water till you get to just a bit under the half way mark on the glass. But siphon it into gallon jugs.
This I'll bet gives you a fair total of what you took out and you double it to see what the total water volume is. Now tell me you have a sump and we really have a problem in
the figuring...LOL...
Just an idea how you might get a fairly close total.
I use the EI, but only one dose of it because I don't use CO2 just Excel.
I likely should be using the level for 10g since I'm leaving off two doses.

The shortest distance between any two points is a straight line...in the opposite direction...
Raymond S. is offline

Old 06-01-2015, 03:13 PM
Algae Grower

Join Date: May 2015
Location: Kittery, ME
Posts: 103
I would measure your tank dimensions, measure the height from the substrate to the waterline and calculate a volume that way. Then subtract for what you estimate the volume of all decorations are.
jonsnow is offline
Old 06-01-2015, 03:20 PM
Wannabe Guru

Join Date: Jun 2014
Location: Nj
Posts: 1,137
I just go with tank volume. I think we over analyze things some times.
Old 06-01-2015, 03:35 PM Thread Starter
Planted Tank Enthusiast

Join Date: Jan 2015
Location: Carmel, Indiana
Posts: 601
I was thinking along the lines of saving ferts, by not overdoing it.
benealing is offline
Old 06-01-2015, 03:37 PM
Planted Member

Join Date: Oct 2013
Location: Vicksburg, MS
Posts: 175
I use teaspoons instead of grams. Put too much fertilizer in, I get too much plant growth. I back the fertilizer off for good plant growth and no algae. Each tank could be different, but this works well for me.
johnpfaff is offline

 Tags None

Message:
Options

## Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.

User Name:
OR