FAST-TRAC Dyes are a highly concentrated leak inspection dye that dissolve rapidly in water and provide a vivid fluorescent color detectable in murky water, sewage or effluent. FAST-TRAC Dyes are excellent for tracking and tracing various flows in sewer lines, septic tanks, piping systems, underground streams, lakes, ponds and liquid systems. The dyes also allow for the analysis of the flow of the liquid. Color will last 24 - 36 hours under direct sunlight. They are safe for marine use and they are nontoxic and biodegradable. FAST-TRAC Dyes are available in fluorescent yellow/green (LTDG), fluorescent red (LTDR) and non-fluorescent blue (LTDB) liquid form. Recommended for: Tracing Plumbing and Leak Detection Tracking Storm and Sewer Drains Lake, River and Pond Studies Power Plant Piping Tracing Well Water Tracing Pollution Studies Septic System Analysis Flow Mapping Rate and Volume Analysis Retention Time Studies Decorative Effects in Fountains, Ponds and Streams