Sarah from Illinois writes
Most colorants do not have any toxicity to aquatic life or any area you are treating. The Mark It Blue does not state specifically whether you can use in in an aquatic area. You can contact the manufacturer to see if it will meet your needs. Monterey Lawn:1-559-499-2100
If you are trying to change the color of your pond/lake you may want to look towards Crystal Blue Black Out or Crystal Blue Pond Colorant.
Answer last updated on: 05/26/2013