With all the information already mentioned in this thread and you still can not figure it out, I suggest you get someone knowledgeable in plumbing to install it for you. Just to summarize, here are the materials you need.So for my 55 gallon tank would a 20 gallon tank be good enough for the sump? And also what would I need to get for it?
Standard sump has three chambers. Intake, refugium, return
Even the makers of that overflow box recommend using a tank with a built in overflow. That has to say something. And the pump is only used to prime the syphon not to maintain it.
Anyone ever heard of an iwaki return pump? Its about 822gallons per hour at max 8.2ft