Get to the bottom of that leak! Leak Speak Tracer is perfect for thermal fogging leak tracing, non-toxic and biodegradable. Leak Speak will not harm fish or wildlife. It does not contain glycol or any other toxic additives, so it can be used safely in river and pond studies. Fog Leak Speak Tracer in piping to trace, track, and analyze conditions in residential, commercial, and environmental applications i.e. storm and sewer drain tracing, lake, river and pond studies, power plant piping tracing and septic system analysis.