Return pump GPH and headloss confusion...

SomeHappyFish

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Tank 36x12x12 (22.4G)
Sump 12g (RS-75)
Overflow Max Flow Rate 600GPH
Return pump pvc size = 3/4 inch

Question 1:
BRS Says I need a 5x - 10x flow rate do I calculate Tank only Gallons or Tank + Sump Volume ?

Question 2:
If I calculate tank + sump, my sump isn't really 12g since its not filled to the brim, I cut the volume in half ?

Question 3:
Head pressure lost... BRS calculation gives me a
4ft vertical + 1.75ft horizontal + 4x 1ft (90 Elbows) + 4x 0.5ft (45 Degree Fittings)
4ft + 0.175ft + 4 ft+ 2ft = 10.175 ft

While another calculator on the web givers me a 4ft head loss with the same values

I'm f@cking lost...
 

blaxsun

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Return pump: 3-5x flow.
Powerheads: 10-20x flow.

Yes, if you have 4x 90° elbows and 4x 45° elbows, that's roughly 6 ft of head height. I wouldn't worry about the horizontal run (probably not very much).

I run 650-750Gph in my 200-gallon system, so trust me when I say that you need a fraction of that (600Gph will turn your tank into a literal snowstorm).
 
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SomeHappyFish

SomeHappyFish

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Return pump: 3-5x flow.
Powerheads: 10-20x flow.

Yes, if you have 4x 90° elbows and 4x 45° elbows, that's roughly 6 ft of head height. I wouldn't worry about the horizontal run (probably not very much).

I run 650-750Gph in my 200-gallon system, so trust me when I say that you need a fraction of that (600Gph will turn your tank into a literal snowstorm).
Headloss.PNG

Now if I had this to my height = 45 (3.75ft from floor to Return Nozzle)
I get 4.05ft of head pressure loss... So if I get this right I need a pump that can give me 172GPH at 4ft of height ?
 
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SomeHappyFish

SomeHappyFish

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Probably something between 150-250Gph (net).

I'll assume you double-checked the math... My advice is get a DC return pump with controller (variable speed), so you can throttle up or down if need be. Probably something between 150-250Gph (net).
So this model Jebao/Jecod DCS-1200 DC Waterpump 320gph 4.9ft would be more then enought ?
 
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SomeHappyFish

SomeHappyFish

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As I indicated, you'd need to run the numbers with respect to head loss, etc. and see if it falls within the range I suggested.
if I insert the 320GPH into the calculator (5.3333 Gallons per minute) is gives me a 1.2ft head loss now, then I add this number to my height 3.75ft and it gives me 4.9ft of head pressure at 320gph (or 5.33 gpm) which is good for my setup ? Since the pump describes giving 320gph at 4.9ft
 

BeanAnimal

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No need to over complicate. You want a DC pump that will do ~150 - 200 gph at round 8 feet of head, that will give you plenty of pump to amp up and down for ha size tank. A step up will not hurt either, run on a faction of its capacity. It will run cool and forever. Reef Octopus Varios are nice and a decent price.
 
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SomeHappyFish

SomeHappyFish

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No need to over complicate. You want a DC pump that will do ~150 - 200 gph at round 8 feet of head, that will give you plenty of pump to amp up and down for ha size tank. A step up will not hurt either, run on a faction of its capacity. It will run cool and forever. Reef Octopus Varios are nice and a decent price.
The pump linked would work ?
 

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