Sphagnum and peat moss together is ok, but I heard that some firs have a natural posion to them that might cause you some trouble. I can't for the life of me remember where I read that though. I am sure someone else knows more.I got this Fir and Sphagnum peat moss mix or subsrate, it says it is ideal for frogs, anoles, geckos, skinks, snakes and toads. Just wondering if the fir is okay?