Beguinners siple questions

Klaus H

Junior Poster
Mar 9, 2008
Hi guys!

First of all i want to introduce myselfe:

My name is Klaus Herold. I livein Austria and work as a pharmacist, so i do have alot of knowledge about chemistry which helps alot i guess.
I have read along this forum and since i am getting my new tank next week and i still have no clue on some things i have some questions. I am not an absolute beguinner since i have had fish since the age of 6, however i did never have a hightech planted aquarium so far.

I want to have a planed tank with discusfish.

My tank is of a sice of 160cm x 70cm x 70cm sice which is about 780 liters.
I have 4 tubes of 80W T5 lights and a pretty good CO2 system with ph controll.

My first question is what you guys think about a substrate heater and which dimension it should have for a tank of this sice.

I read alot about "EI Excel" dosing here. However i couldnt find out what that is so far. Please bring some light into that misterium. I understood that Excel is some kind of no CO2 dosing. However, whats EI?

As i am from Austria i do not have access to ADA soil or something like these substrates. i can only go for dennerle or JBL substrates. Have you guys any experienes with these substrates?

thanks for your help
yours Klaus


Lifetime Charter Member
Lifetime Member
Jan 24, 2005
Sacramento, CA
I think you have enough light intensity to grow almost any plants you wish to grow. Substrate heaters have not been shown to help grow plants, so I suggest not using one. EI is an abbreviation for "Estimative Index", which is a fertilizing method described in detail in one of the forums here. A simple description of that method is that it involves dosing more than enough of all of the nutrients the plants need, then replacing about half of the water in the tank once a week, to limit the build up of excess nutrients. This method doesn't require testing the concentration of nutrients in the water, or trying to calculate exactly how much of each nutrient is needed.

EI and some other fertilizing methods are designed for use with potassium nitrate (KNO3) to provide potassium and nitrogen, mono potassium phosphate (KH2PO4) to provide phosphorous, and one of several trace element mixes to provide the other nutrients. But, it works with commercial aquatic plant fertilizers too.

I have no experience with either Dennerle or JBL substrates.

Klaus H

Junior Poster
Mar 9, 2008
Thanks VaughnH for your quick answer. I have read up the Estimated index articles you mentioned. I think i will use this method in addition to some tests to optimise my fertillisation in a later stage. maybe i am going to mix my own ferts to get cheaper off because it can get quite expensive if you have 780l water to treat every week.
i am going to overthink the need of a substrate heater again. in germany and austria these substarteheaters are very common, however you dont find alot of them in those beautiful nature aquariums. thats why i asked about them. maybe i should invest this money in even more plants.

cheers klaus

Tom Barr

Staff member
Jan 23, 2005
Substrate heaters are popular there because the companies that sell them have marketed them well.

Not because they work. However, heating cables also do not harm a tank and they do warm the tank, but this may be done using a regular heater just as well.

In many places, it's just way to hot/warm to use them most of the year. In these places, no one reports any growth differences when = on/off.

If they actually worked as claimed, we would see growth differences when they where on/off over time.

But no one ever has that I know nor have I been able to show that they help or harm any aquarium after 10 years and I used 7 aquariums with cables.

There is a good site in German,
Toby is a nice guy and and it might be easier to read and talk.

Tom Barr