Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
It is intended for gardens, pots and so on, not aquatics.
If you have a plant-only tank, I do not see how it would be a problem. Small dose!
I would not risk fish or other livestock.
Read the product label. What is the source of each fertilizer element?
Then come back to this site and see what other people have said about using that material in an aquarium.
For example, is Urea one of the sources of Nitrogen?