return flow question

It's a matter of personal preference with some functional annotations. What does a sump do? Well, generally it agitates the water to improve oxygenation, distributes water to various filtration devices; activated carbon, mechanical filters, gfo, skimmer, and provides some amount of water flow at the top where it is returned although this is not usually it's primary function. In a softie tank, the need for these various filtration devices is minimal, active carbon or skimmers are great because they remove some of the compounds each coral secretes to inhibit the growth of others, but generally moderate amounts of organic matter aren't of much concern in a softie tank. In an SPS tank all of the filtration components are essential to maintain healthy specimens, but a balance must be struck between cycling the water such that enough water is filtered/hour/day/week/mth etc. and that the water cycled through the sump has sufficient dwell time for water through the sump to react with the filtration components. Obviously, pending the types of devices and flow rates of each filtration component the optimal flow rate will be variable in the system, but generally speaking 10x turnover/hr is usually the recommended sump flow rate for most tanks, including sps tanks, and you can bet that if it's good enough for sps it will work for softies too!

Cya,
Andy

 

What kind of skimmer are you going to be using for this tank? How many gallons per hour can it process? Let's say your skimmer can process 500 gph. Do you really want to send 5,000gph into it or your sump? At that rate, your skimmer wouldn't keep up and you would be sending a lot "dirty" water back into your display again. There are a lot of guidelines out there for sump turnover but the one that makes the most sense is 3X-5X turnover. Anymore seems to be a waste of energy.