Just a quick explanation, than please let me know if this would work or what you would change. Thanks!
In the drainage barrel, I will have the drain pipes pour in with filter socks over them and may have them drain into a 5 gallon salt bucket with holes within the barrel, which will reduce micro bubbles. There will also be another barrel to the right, which will usually be empty, except for when I'm doing a water change. There will be a ball valve that I can turn on to easily drain water into this barrel to drain 40 gallons out for the water changes
In the next barrel, I will have my protein skimmer attached within there.
The water will then flow into the next barrel down, which doesn't really have a purpose other than to make it easy for me to expand water capacity, make the water changes with the attached barrel to the right, and to divide the flow in two so I can slow it down for the refugium.
The barrel to the right will hold newly mixed RO/DI saltwater for water changes. There will be a closed valve between them, which I will easily just turn on simultaneously with the other valve that drains to the empty barrel from the first barrel to do easy water changes. There will be a flow restrictor so that only the new water can only go out of that barrel.
I than divide the flow for the barrels to the left so that the long pipe will go straight to the end barrel that will return to the main tank. The other split, which I'll be able to control the flow of with a valve, will go first to a covered barrel that will be almost full with sand for nitrate reduction. That will then drain into the next barrel that will host live rock and macro algae with a light above it for pod growth and more nutrient export. That will then finally will flow to the return barrel as well.
