Thought I'd say hi and say I've found this thread very interesting indeed. Having spent an absolute fortune since starting fishkeeping last year, it's great to see the success you've had on a budget.
So I don't get over excited and try doing this with my tank, could you please fill me in on your water ph/kh/gh to see if I'm similar.
You might notice some driftwood I found DOWN BY THE RIVER (not in a van though). I boiled it and was gonna soak it like the Internet said to, but since it was literally driftwood that I pulled off the bank of the Snake River, it was already waterlogged enough that it sunk! Some of the sticks I got though must have dried out a bit on the shore since they wouldn't sink.
Hopefully someone more knowledgeable will correct me if this is wrong but boiling helps kill off any parasites / nasties that are in the wood, as much as helping it sink. I would definitely still boil stuff, whether it sinks or not.