So I this is the first time I've done a yeast starter. Now the pro-culture yeast vial I have has been sitting in the fridge for at least two years so I know there is a chance that it may not be viable. But I did a small starter of 500ml with a stirplate. I've just stepped it up to 1000ml after about 3 days and before I stepped it I took this photo. Is this yeast still healthy enough to use or will it be a lost cause? What are people's opinions/suggestions???