H2O2 has seeped into the substrate granules so what plants do not get nutrients no more - all that it gets is H2O2! unfortunately the soil cannot be recovered anyomre as aquarium is a captive system and once an imbalance comes in it's gone i'm afraid. Changing the substrate and starting all over is the only option left now.
Good judgement comes from experience, and experience comes from bad judgement.
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