Has anyone ever heard of using this as pond dye?

it will work but probably cost more than dye , we have 4 packets for $5 and that is equal to a gallon.

I can get a case for 175, or 14.50 a quart. Is this just as good as pond dye?

for that price I say give it a try. no idea of its stength.

I'll try it this weekend.