FAST-Trac LTDG16 Leak Tracing Dye 16 oz - Vivid Yellow Green

Our review of the FAST-Trac LTDG16 liquid leak tracing dye finds it best suited to professionals and serious DIYers who need a powerful, easy-to-see tracer for plumbing, sewer and environmental flow work. The single biggest reason to buy is its industrial strength formulation that remains vivid even when diluted, allowing one 16 fl oz bottle to treat up to 12,500 gallons and reveal leaks or cross connections that are otherwise invisible.

Key Features

• High concentration: The industrial strength formula is marketed as 4X stronger than retail brands, so small doses produce a vivid fluorescent effect in large volumes of water.
• Long visible life: Color remains detectable for 24 to 36 hours in direct sunlight, giving technicians time to locate and document flows.
• Versatile tracing: Designed to trace water, sewage, septic lines, and storm drains, the dye works in murky water and effluent where ordinary tracers fail.
• Large treatable volume: A 16 fl oz bottle treats up to 12,500 gallons, which reduces the number of applications needed on large systems or bodies of water.
• Safe for many uses: The dye is nontoxic, biodegradable, and safe for marine use, allowing use in ponds, lakes and sensitive environments without persistent contamination.

Who It's For

This product is aimed at plumbers, sewer contractors, environmental consultants and utility crews who need a professional grade tracer for locating leaks, testing toilet tank seals, or tracing cross connections in complex piping systems. The vivid fluorescent yellow green color and high concentration make it especially useful when visibility is poor and when large volumes must be treated.

It is less appropriate for casual hobby craft use where nonfluorescent or fabric-specific dyes are preferred, and buyers who need colored dye for textiles or permanent staining should look for products formulated specifically for fabric decorating rather than a concentrated tracer designed for liquid systems.

Pros & Cons

Pros

• Highly concentrated so small amounts treat large volumes, cutting down on product use and handling.
• Fluorescent yellow green is easy to spot in murky water and sewer flows, simplifying detection work.
• Biodegradable and nontoxic formulation allows use in ponds, lakes and marine settings with less environmental concern.

Cons

• As a specialty tracer, it is not formulated for fabric dyeing or permanent coloring of materials.
• Color longevity is limited to about a day in sunlight, which may require timely inspection after application.

Specifications

Our Verdict

The FAST-Trac LTDG16 is a practical, cost-effective choice for professionals who need a strong fluorescent tracer that performs in real-world plumbing, sewer and environmental applications. Its high concentration, safety profile and clear visibility make it good value for fieldwork, though those needing fabric dyes or permanent stains should choose a different product.

Frequently Asked Questions

How much water will one bottle treat?
One 16 fl oz bottle treats up to 12,500 gallons when used at recommended dilutions.

Is the dye safe for ponds and lakes?
Yes, the formulation is described as nontoxic and biodegradable and is safe for marine use, suitable for environmental tracing.

How long will the color remain visible?
The fluorescent color typically lasts about 24 to 36 hours under direct sunlight, so inspections should be planned accordingly.