They are tilapia. About the toughest fish you can raise in an aquaculture system. I would leave them be, and see what happens. Ph is tough to work with, even tougher when you have green water. I would see how they grow, and feed. Your ph is not ideal, but it is not going to be a deal breaker. You have bigger fish to fry. Get that filtration squared away fast, Minimal feed right now. Your tilapia are feeding this very minute on that green water,and that greenwater is filtering waste. Once you start feeding them enough feed to make them grow, your water quality will suffer. So stick with minimal feed for a couple weeks, then gradually increase your ration.
