Walstad Nano Tank Using Mineralised Top Soil Method

Discussion in 'Members Fish Tanks' started by Balian, Apr 9, 2019.

  1. Balian

    BalianNew MemberMember

    Hi All,

    I set up a new nano aquarium (20L) this weekend, based on the principles of a Walstad tank but with a mineralised soil substrate as opposed to the typical "Miracle Gro Organic Choice Potting Mix". The steps I took were:

    1. Purchase some cheap top soil and mineralise it over two weeks or so in the sun.
    2. Remove any large particles and twigs (this helps prevent algae). The result is a very fine sand-like texture with no scent whatsoever.
    3. Mix in 10% of red clay to provide iron. Add water to form a smooth runny mud.
    4. Add a layer of 'muriate of potash' to the base of the tank. This provides the potassium to the substrate.
    5. Add a second layer consisting of the runny mud. (1 inch)
    6. Top with gravel to create a nice seal. (1.5 inch)
    7. Plant heavily to minimise the risk of an algae bloom.

    The only thing inside the tank is a heater, no other equipment - no pump, no filter, no CO2, no ferts. It's only been a few days but so far I've seen very few signs of algae and I was shocked to see new shoots growing out of my hornwort already. I've even seen a fair amount of pearling on the leaves after day three!

    I've attached some pictures to show how it looks:

    Mineralised top soil mixed with clay:


    First Layer (Potash):


    Second Layer (Soil):


    Third Layer (Gravel):


    After Planting:



    Plants used: Hornwort, Egeria Najas, Rotala Indica, Bocopa, Dwarf Hairgrass

    What do you guys think? I know it's early days but I'll post some updates to show how it progresses. It was something of an experiment and I look forward to seeing how it unfolds.
  2. Coradee

    CoradeeModeratorModerator Member

    Wow if your tank looks this good & you’ve only just started can’t wait to see what it looks like once it’s established!