"Why not use a surfactant that is made for the application?"Because I don't know things lol, I will get one for this application
"What rate did you apply the Diquat?"
I realized that this was my problem soon after I posted my question. Through my google research I learned that aquatic applications require much more per gallon of water than land applications. I just sprayed again and at the correct rate this time

Forgive my ignorance, I'm still new to all this stuff haha. I really appreciate the people in this forum for being so helpful and nice, especially to newbs like me.