Hello and welcome
It is likely that the bits of floating white stuff are the build up/combining of the nutrients in the mix.
I have seen build ups of particles within other liquid and gel fertilizers. Especially build up of residue around the container opening, where some of the liquid may end up resting and then evaporates to leave a salty textured substance.
The trick to reducing this is to not have the container open longer than it needs to be. Also shaking the container well before use, should help keep the solution dissolved.
Just my
, and it's possible I'm wrong in thinking this.