Re: Woods that are safe for darts and microfauna?
Manzanita works well, and I've used java wood, ghost wood, and mopani wood in tanks also.
Grapewood is safe, but rots really quickly. If you're using it non-structurally, and plan to allow it to turn to mush, you can probably incorporate it into a tank with frogs. If I were going to do this, even then I would use it sparingly, for that matter. Otherwise, I might reserve it for use as edible furniture in an isopod master culture.
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