I have a wood burning insert in our fireplace. It gets continual use 4-5 months out of the winter. The brick hearth gets rather dirty and discolored. I am looking for suggestions or a "how to" on cleaning this brick. Someone suggested some sort of acid but I've got two very active toddlers and no experience working with that kind of stuff. Any ideas would be much appreciated. Let me be clearer...any GOOD ideas would be helpful! Ha ha...uh. Anyhow...a warm thanks in advance!