Hi!
Watery fluid (dried or drained) is a sign of an irritation in the eye. If it is a one-off; then the irritatant has likely been washed out.
If it is ongoing or there is repeated squinting, then please see a vet for either something stuck under the lid or a cut to the eye surface that is invisible to the naked eye. I could also be a sign of a beginning conjunctivitis, but that is for the vet to decide.
The regular eye cleaning fluid is a milky white. Occasionally you can see white flecks hanging around the eye that have not drained properly through the tear duct.
Any thick green/yellowish crust are a sign of a well developed respiratory infection (URI) and need to be seen by a vet promply as that is a potentially fatal bacterial disease.