It's the Carib sea black sand. I'm doing Flourish liquid dosing from sea chem and maybe root tabs if I need them. I've had the Java fern and Anubis for ever, it does great no matter what lol. Though I want to get into more challenging plants, stuff that fills out and has bright greens.
I have the Carib sea planted dirt mix in my 15g and the plants love it. (I almost did that instead of the sand in the 29, but I'm a sucker for the look of sand)
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