Advice for GPH

[Birdman Broham]

I currently have a 520GPH with a 2 1/2 ft flexible hose as a return line. No bends, just a straight shot. My tank is 75 gallon with a 12-16 gallon sump. Is my return pump big enough? I feel like the flow isn’t that strong or maybe I’m overthinking it. Anyone with knowledge please chime in and suggest a different size or if mine is big enough.

 

[blaxsun]

Assuming your tank size is roughly 90-gallons, you want a return flow of somewhere between 3-5x volume, ie: 270-450Gph. The 520Gph rating for your pump is at 0 head height, so you'd need to look up the performance chart and figure out the head height based on the vertical distance, # of 90°/45° elbows, etc. Just from the images I suspect you're probably seeing a -50% hit in pump efficiency.

 

[Birdman Broham]

I have no pvc, therefor there is no elbows, 90s etc. It’s a flexible hose that’s 3/4 thick and about 2 1/2 feet long.

 

[dwest]

I have no pvc, therefor there is no elbows, 90s etc. It’s a flexible hose that’s 3/4 thick and about 2 1/2 feet long.

The pump is fighting the head pressure of the height of water it is pumping as well.

You can measure the flow of the return line to see what flow you have and go from there. I bet you are getting 200-400 GPH which is fine IMO

 

[exnisstech]

I wouldn't even worry too much about gph on your return. It's pretty much just for filtration and flow through a fuge if you have one. I depend on powerheads for the flow in my tank. I may be doing it wrong but it works for me. I have 3 systems running and couldn't tell you how many gph any of the return pumps have.

 

[Birdman Broham]

The pump is fighting the head pressure of the height of water it is pumping as well.

You can measure the flow of the return line to see what flow you have and go from there. I bet you are getting 200-400 GPH which is fine IMO

How would I measure it? Thanks for your response

 

[dwest]

How would I measure it? Thanks for your response

Can you put the return in a 5 gallon bucket? If so, a bucket and a timer.

 

[Birdman Broham]

Can you put the return in a 5 gallon bucket? If so, a bucket and a timer.

And see how long it takes it fill it up or what? Sorry I’m new

 

[Thumbster]

Yes. And at the same height as it is when going into the tank.

 

[dwest]

Yes.

But as one member stated your flow is probably fine and you could also not worry about it.

Or, if you give me the pump make and model I might be able to estimate flow.

Or you can measure the flow. For example: It takes 1 minute (0.017hrs) to fill a 5 gallon bucket halfway (2.5 gallons) from your return line.
2.5 gallons/0.017 hrs~150 gallons per hour or 150 GPH

 

[Mr. Mojo Rising]

are there any powerheads in your tank? Or you just rely on the return pump for flow in the display tank? Personally I would definately get some powerheads in the tank. With just the return pump alone must have so many dead spots in the tank.... I have about 30x-40x turnover rate in my tank

 

[Birdman Broham]

Yes.

But as one member stated your flow is probably fine and you could also not worry about it.

Or, if you give me the pump make and model I might be able to estimate flow.

Or you can measure the flow. For example: It takes 1 minute (0.017hrs) to fill a 5 gallon bucket halfway (2.5 gallons) from your return line.
2.5 gallons/0.017 hrs~150 gallons per hour or 150 GPH

JEREPET 520GPH 20W 9FT Aquarium 24V DC Water Pump with Controller, Submersible and Inline Return Pump for Fish Tank,Aquariums,Fountains,Sump,Hydroponic,Pond,Freshwater and Marine Water Use https://a.co/d/8eay9hS

 

[Birdman Broham]

are there any powerheads in your tank? Or you just rely on the return pump for flow in the display tank? Personally I would definately get some powerheads in the tank. With just the return pump alone must have so many dead spots in the tank.... I have about 30x-40x turnover rate in my tank

Yea. I got a icecap 1K and a hygger 720GPH

 

[PotatoPig]

How would I measure it? Thanks for your response

The product info for the pump will likely have a little chart on it showing GPH vs return height (measured from the water surface of the sump to the water surface in the DT). What return are you using?

 

[Birdman Broham]

The product info for the pump will likely have a little chart on it showing GPH vs return height (measured from the water surface of the sump to the water surface in the DT). What return are you using?

 

[dwest]

I couldn’t find a pump curve for that pump. But for similar sized pumps with the 3 ft of head (you gave the height as about 2.5ft), a very rough estimate is 250 GPH. I think you are good.

That pump is DC which means you can control the flow. So if it’s not at 100%, you can increase the controller output to increase the flow if desired.

 

[Birdman Broham]

I couldn’t find a pump curve for that pump. But for similar sized pumps with the 3 ft of head (you gave the height as about 2.5ft), a very rough estimate is 250 GPH. I think you are good.

That pump is DC which means you can control the flow. So if it’s not at 100%, you can increase the controller output to increase the flow if desired.

yea its at 100%