Potting soil as a substrate in planted tanks

Ammy

Small Fish
Apr 3, 2009
26
0
0
#1
I have been reading a ton about planted tanks recently. I want to set up a nano for a summer hobby, but I am also thinking of starting up my future tank as a planted tank. I have read about using potting soil as a substrate, and I think I'm going to go with that method, but I keep running into an unexplained thing. Each time I read about someone using soil, they also they that they add some crushed coral or crushed oyster shells. I assume this is for the Ph, but I am not sure. Anyone know what this is for, and if it is necessary?
 

brian1973

Superstar Fish
Jan 20, 2008
2,001
3
38
Corpus Christi, Texas
#2
dont go with "potting soil" use garden soil without ferts or manure, alot of "potting soils" are actually compost so there is very little mass to them. I currently use lowes garden soil with a layer of Lowes pea gravel in my 90G planted tank. high lighting and NO CO2 and the growth is amazing. As for the crushed coral or shells I cant comment on that because I dont use it. You do want to top the soil with gravel or maybe sand to basically hold the soil in place. Now be aware that you may get some blue/green algea in the gravel if that is something that is going to bother you i would look into commercial aquarium soils such as flourite or eco complete.

If you check out NANFA.ORG forum there was a thread discussing this topic yesterday I believe, You can also find my 90G planted tank thread in the planted forum here on MFT where I show progress from start to sometime in march I believe. I will link it if I can find it.
 

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Ammy

Small Fish
Apr 3, 2009
26
0
0
#3
Thanks Brian, that is some good advice! I'm glad you distinguished between "potting" and "garden" soil. Does garden soil stain the water at all, in your experience? I know I can test it out, but just curious.
 

brian1973

Superstar Fish
Jan 20, 2008
2,001
3
38
Corpus Christi, Texas
#4
No..no staining at all, even when I trim and replant I get very little soil in the water column, no cloudiness, just make sure you use 1" of gravel, just FYI I spent less than 20 bucks on my substrate in my 90G and it is anywhere from 2" to 4" of soil then approx. 1" gravel.

I am moving and the problem I have right now is figuring out how to remove the soil without mixing the gravel into it to where it is useless. According to NANFA soil already contains the bacteria required to cycle so you should have little or no cycle period, watch this for yourself but mine didnt have to cycle.
 

ishar

MFT Staff
Jul 27, 2007
1,490
0
36
33
Hamilton, ON.
#5
I use soil in my tanks, and the growth is amazing, but I made the mistake of using less than an inch of gravel. Soil tends to get swished into the water by fish and I have soil settle on the leaves of my plants, causing an odd algae to grow, one I have not been able to identify using internet resources so I assume it is one directly related to the soil. The growth is amazing and the cycle is minimal, but as I and Brian both said, make sure you use enough gravel on top.
 

Ammy

Small Fish
Apr 3, 2009
26
0
0
#6
Sounds great! I was kind of daunted by all that I was reading until I came across the soil method. These little bits of advice are really going to help. I have read about the nice cycling benefit, but yeah, I will keep an eye on things, especially the ammonia since I have read it can leach out of some soils. Is it really possible that you don't have to use CO2 if you're using good soil? What do you guys recommend?
 

brian1973

Superstar Fish
Jan 20, 2008
2,001
3
38
Corpus Christi, Texas
#7
i havent had time to search for my 90G planted thread but you can see the growth difference over the beginning and about 2 months later, I DO NOT use CO2, I use 260W PC lighting. Now my growth may be faster if I had CO2 but if it grew any faster I would do nothing except trim plants.

So now that i rambled the simple answer is yes it is possible to have a lush planted tank with using soil and NO CO2.
 

ishar

MFT Staff
Jul 27, 2007
1,490
0
36
33
Hamilton, ON.
#8
Diana Walstad wrote in her book 'ECOLOGY of the PLANTED AQUARIUM - A Practical Manual and Scientific Treatise for the Home Aquarist' that adding CO2 depreciates the length of time the soil will be useful for the plants. I do not remember the reason and my book is packed away from a move, but I believe it has something to do with the iron in the soil reacting with the CO2 in the water column. This would happen naturally anyways but at a much slower rate than with CO2 injection.

I use CO2 injection and so far I have found the growth to be phenomenal.
 

Jan 21, 2017
28
0
1
#13
I have been reading a ton about planted tanks recently. I want to set up a nano for a summer hobby, but I am also thinking of starting up my future tank as a planted tank. I have read about using potting soil as a substrate, and I think I'm going to go with that method, but I keep running into an unexplained thing. Each time I read about someone using soil, they also they that they add some crushed coral or crushed oyster shells. I assume this is for the Ph, but I am not sure. Anyone know what this is for, and if it is necessary?
Woah woah woah! Dude do not put potting soil in your tank. It must be clean and fresh water. If dirt is floating around all the time; without a doubt your fish will die.
 

FreshyFresh

Superstar Fish
Jan 11, 2013
1,337
23
38
East Aurora, NY
#14
There are various plant soils that indeed can be used in an aquarium and are typically capped with another substrate to keep it in place. It's common for folks in the hobby who are into serious planted tanks to run "dirt". I personally would rather drag my arse through broken glass then do this, but it can and has been done countless times.