My horse has blue eyes, the eye that is surrounded by white hair only has always been the gunkiest eye. He wears a full face mask in summer which helps with keeping it clean and shaded, that eye is much more sun sensitive than the other. I wipe his face down every other day with baby wipes and try and keep that eye as clean as possible. I have eye cream from the vet which I keep in the fridge and use that whenever the skin directly around his eyes looks irritated. His nostril on the same side always has more gunk in it than the other side too. White faced horses can be quite time consuming, especially when they've suffered really bad sunburn in the past.