I wouldn’t use potting soil as a substrate in any of my tanks. Most potting soil contains high amounts of nitrogen and phosphorous to encourage plant growth and I’m a little concerned about the frogs absorbing it. … I use a combination of Eco earth and top soil (not potting or garden soil), I then add a layer of Sphagumn Moss and leaf litter, it works for me. I have some tanks that have a true false bottom built and some with LECA only, I have had very few problems. …

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