can I add iron in the form of rust?
like, putting rusty steel bolts in the substrate and a few in the canister filter
steel's a mix of iron, chromium and carbon ... I'm not sure about the chromium in the tank, I don't know if it's toxic or not
like, putting rusty steel bolts in the substrate and a few in the canister filter
steel's a mix of iron, chromium and carbon ... I'm not sure about the chromium in the tank, I don't know if it's toxic or not