O am currently working on a dual corner overflow. A marineland 125g. I will be soft plumbing it for the most part. I will be using some hard plumbing also. But I tend to over think on stuff. I want to keep keep it simple. I am having problems coming up with ideas on a manifold design. I do plan on gate valves on the manifold. Looking for ideas. Also I will not be combing the drain lines together. In keeping them separate.