Can I use a product called "Liquid Lightning" 20 oz drain opener in a basement floor drain? House built in 1974, I believe the floor drain is made of cast iron. Product says it contains virgin sulfuric acid with twelve buffers. My washing machine drains into this floor drain. If not, is there a floor drain opener you recommend for this that won't hurt pipes? Thank you very much!

I am no fan of putting harsh chemicals in your drainage system. Especially drain cleaners containing sulfuric acid, I lost a good friend when he poured "Blastb OUT" drain cleaner containing sulfuric acid into a open closet bend in a small unventilated bath room. I would stay away, way away, from using anything with acid in it. If you want to know the best drain cleaner? It's called a snake. Good luck, Tom

I agree completely, Tom. Best, and really only good bet is to auger the drain.