just got a new tank 8'x2'x2' and it has about a 20-30 gallon diy sump under the tank. theres a hole drilled on the left side for the overflow, and pvc going to the sump. theres also a gravity fed hob protein skimmer that connects with the overflow pipe. i want to redo the whole filtration and piping. what is the best size pipe to get for the overflow and the the filter, also what size check valve. i also need to get a new pump, what kind of pump should i get and what will be the best to filter out my tank. i can always up grade to a bigger rubbermade.