@MaloK I get the new tank new wood set up & using carbon then. But I have to say I have some "well loved" old wood I've used off & on for years. Way past leaching tannins or anything else much.
I soak new wood with several water changes & call it good enough. Maybe more with wood collected in the "wild". No telling what it may have been exposed to even from my drinking water reservoir. It's funny, my husband & I walked around our old "rez" looking for some big wood for a new tank. We found a nice big 4 or 5ft piece actually in the water. Carrying it back to the car we heard "I hope that's going in a fish tank". So of course we stopped to chat. By the time I removed the soft rotted parts with a Dremel & metal brush it was down to 2 smaller pieces, darn! It smelled like cherry maybe. So, I researched & it would (wood? lol) have been safe but I chickened out using it.
Now I have a nice big piece of manzanita I was given before covid. I've soaked it but it doesn't all fit in a tub at a time. Then we had wildfire smoke & it smelled of it soon after. So, I'm thinking I may put in my no fish plant tank with carbon before I risk fish with it.
No MaloK, I don't think you're the only 1 using carbon all the time, but I'd like to know what others do...& why.
Sorry
@Billybong1 if this seems to hijack your thread. I think it's related enough to your original question to merit more discussion. I hope you think so too, it's how we all learn
A belated welcome!