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Clay as a subsoil???

2799 Views 12 Replies 7 Participants Last post by  Glouglou
I wonder if the use of a mix of clay, laterite with a small amount of sand against compression. (maybe with a small amount of peat and crush marble or oyster shell) spread on the bottom as a 1/2 to 3/4 inche layer can be a good subsoil?
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Clay particles can stay suspended in water for thousands of years, so bad idea. Unless you mean a clay product, such as flourite, soilmaster, or otherwise fired or whatever.
Clay and particles...

Clay will stay put until your stir it up. Red Art clay and others type of clay are use already in subsoil or in nutrient balls at the base of plants. They have the properties to clarified the water. You will have particles in suspension only when reaching deep in the substrate and anyway they will settle down.The idea here is to build an high level nutrient bottom layer.
I used clay (or was it loam?) during the first years of my 100gal tank, topped off with pea gravel. Initially it worked well, except that each time you pull out a plant with lots of roots, you better have some good filtration (DE?) or patience.

After a couple of years, the layer hardened, so it was rather difficult to plant bigger plants. Now I use a fired clay substrate, like Flourite, over a layer of peat, and so far it works better.
I use clay mixed with a mineralized top soil (95% soil 5% clay), the clay acts as a flocculating agent and binds the soil particles into larger clumps that settle out of the water faster when you disturb the bottom. I scatter a handful of dolomite and potassium sulfate on the bottom of the tank before I put the soil mix in. My favorite cap is the 3M ColorQuartz, T-grade.
isn't laterite clay?

I have some in my tank.. They do cloud the tak quite a bit though.
I'm not really sure if it has any benefits... But you set up might work pretty well for rooted plants.

You can have an interesting definitinion here.

Laterite, I think is more like hardened, washed-up roc that lost all is soluble elements.

Clay are a weathered mineral but plasticity is one of is major quality. I doubt that laterite have any plasticity.

You can see here a complete chemical composition:

You can see a very high content in iron, small amount of micro element and almost no Ca or mg ( will not change to much GH & KH) a pH of 5.7 , but a low CEC = 2.7 me./100g

Cation Exchange Capacity (CEC)
Some gardeners swear by CEC values, while others grow aquatic plants with nothing but blind faith. It is interesting to know the actual parameters of each substrate, but I've seen plants grown in plain sand and gravel. The samples that lacked at least some organic matter or clay, had slightly lower CECs. The big surprises here were Terralit and Tetra Initial Sticks. The zeolite composition of Terralit provides an excellent ion exchanging medium and has good mineral concentrations. The Tetra Sticks, with it's high organic and mineral content, also had a high CEC. The sandy samples had very poor CECs.
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Hardening subsoil...

My idea is to mix the clay with laterite and a small amount of peat, marble and maybe fritted elements and rare earth. All that, mix with enough inert material like sand or else to keep it to become to compact.

I like to put, say one inch of that stuff (after testing for PH and Water parameter changes) in the bottom of the tank.

Spread a little bit on Sphagnum moss on that follow by 1 to 1 1/2 inche of topsoil follow by 3 to 4 inches of Soilmaster.

The clay and the dirt by their density will stay where they are,
And I maybe like to mixup the Soilmaster with a small amount of gravel or laterite or any other kind of stuff to add nutrient and make it look more natural (I dislike the complete uniformity in the bottom of a thank) I find it unatural.

How you like that cake??

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Nobody like My cake??

Any comments on my recipe.
Maybe a little off topic, but I've recently been researching alternative substrates. Profile makes a "calcined" clay which means a baked clay - sort of like Flourite. Its a lot lighter apparently, and 100 lbs will easily cover a four foot 120 gallon tank. Its $12 per 50 lbs bag and is primarily used as a ball field supplement with good drainage qualities and it also has a high CEC rating according to the Krib. Its called Turface Pro League, made by Profile. I am thinking of top dressing with a larger/heavier Aquarium gravel to give it some mass. I am going to pick up 150 lbs tomorrow morning of the grey colored variety. Bill Harada uses it in his 120 gallon tank. It is suppose to be inert.
Any comments on my recipe.
Nope, have a good time. Keep a photo-log.
Any comments on my recipe.
I have a suggestion. I would keep the soil layer on top of the clay at 3/4"-1" maximum.
Thanks Aaron...

You think 1 1/2 inch will be to much?

To much organic?

I never try a rich substrat before, do you see some problem in my cooking!
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