Our house has sat empty for months. Yesterday we returned to get some things. I ran the kitchen sink, and it wouldn’t drain. I plunged it. Nothing. I poured a half-bottle of Drano Professional or Max or whatever down it. Nothing. I carefully plunged again. Nothing. I poured a few ounces of Marc 55 Drain Cleaner (viz., Sulfuric acid) next. It bubbled some and stank (the room was ventilated), boiled up some nastiness from the depths, but the clog remains.
I see now that I dumped a highly caustic acid on top of a base, hence the bubbling, smell, etc. We’re going back today with a drain snake, gloves, and goggles. There’s maybe 12 oz. of Sulfuric acid and 16 or so oz. of Drano in the pipes. Is there any special danger involved? After 18 hours, has whatever was gonna happen, happened?