Hey, just picked up a 10 gallon tank of craigslist and plan on making it into a sump for my 37 gallon reef project. I am new to this hobby and had a few questions! Heres what i plan to do: i want my sump to be at least 3 chamberer, first one a nice skimmer, second one a refugium, and the third my return pump. I understand how the overflow siphon will work, and the whole plumbing process, im just confused on how much GPH i need to be flowing in my 37 gal. 1. how much gallon per hour should I be planning for? 2. That questions being answered, what size tubing should I be planning for regarding 1. my overflow box, 2. my return pump. 3. I understand a 10 gal has a lot of space restraints, should i just use a HOB skimmer, or one that goes in the water? 4. is it possible to find a good quality skimmer small enough to be productive in my 10 gal sump? 5. Does anyone have a good blueprint for a 10 gal. sump with a refug, and bio filter? 6. I want to buy my skimmer and pump first and then build sump around it, any recommendations on a skimmer and return pump?