It just doesn't work like that – you don't "match" the numbers.
First, both numbers are nominal ratings. Ideal maximums, if you will. Subject to
actual reality at time of installation.
You have to include
some info about your plumbing to get an accurate estimate of the actual flow you wold get from a particular pump in a particular installation.
Can you use something like a bucket and a stopwatch to measure your flow now – either at the drain or return outlet; whichever is easier to get to.
- Time how long it takes to fill a container that will work.
- Measure how much the container holds.
- "how much" / "time" you can convert into the actual GPH flowing through your system.
Here are the biggies for future planning – you need to know these before setting your expectations for any pump:
- How many feet does the plumbing have to go to get from the sump to the top of the return? (only the vertical)
- How many feet is the total plumbing run from the sump to the retrun? (vertical as well as horizontal)
- How many 90º bends will be required to get there? (Can two 45º bends or a special long-radius 90º be used instead?)
- Include any other significant features such as any valves or tees, but hopefully these items above, plus an entrance and an exit, about describes it.
- Simple is better.
The thread is still shy on detals....we need all of the above....plus what pump do you have?
Photos of the tank and plumbing would help too.
But here's what I can tell you so far:
- 1/2" plumbing is going to be incredibly restrictive, even at the low flow rates you need for a 60 gallon tank.
- A 60 gallon tank only requires about 120GPH to 240GPH through the return.
- Beyond 300GPH is beyond overkill, does little for you, and can actually cause problems similar to what you're seeing, as well as noise and bubble issues.
- If your return is 4' high, 5' total, has one 90º fitting, and you have a Quiet One 2200 pump (a "600 GPH" pump), you should be getting 367 GPH.
- If you were to switch up to 1" plumbing for your return, the same pump could deliver about 400 GPH. About a 10% bump.
- The real bonus from knowing this and using the "right-sized pump" is that you could use a much smaller pump which:
- might cost 10%-20% less
- will probably use about 50% less power
The details from me estimating your actual head loss, from the
On-Line Friction Piping Loss calculator...I made assumptions you might have to correct to get good information.
We can help.
Liquid Friction Pressure Loss
Pressure Loss (psi): 0.56 Head Loss (ft): 1.3
Line Number:
Date: 12/3/2016
Nominal Pipe Size: 0.5
Pipe Schedule: SCH 40
Flow Rate (gpm): 4
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 0.622
Fluid Velocity (ft/sec): 4.23
Reynolds Number: 20847
Flow Region: Turbulent
Friction Factor: 0.026
Overall K: 4.58
Piping Length (ft): 5
Short Radius Elbows: 1
Pipe Entrance: 1
Pipe Exit : 1
Liquid Friction Pressure Loss
Pressure Loss (psi): 0.06 Head Loss (ft): 0.1
Line Number:
Date: 12/3/2016
Nominal Pipe Size: 1
Pipe Schedule: SCH 40
Flow Rate (gpm): 4
Viscosity (cP): 1
Specific Gravity (water=1): 1.025
Temperature (F): 79
Pipe Roughness (ft): 0.000016
Actual Pipe ID (in.): 1.049
Fluid Velocity (ft/sec): 1.49
Reynolds Number: 12361
Flow Region: Turbulent
Friction Factor: 0.03
Overall K: 3.65
Piping Length (ft): 5
Short Radius Elbows: 1
Pipe Entrance: 1
Pipe Exit : 1
This might be true for some kinds of pump, but it's not true for any of the kinds used as return pumps on aquariums.
Still, I'm not a fan of using valves to "dial in" a return.
Although valving a pump back will reduce power consumption, using the
right-sized pump in the first place is a better way to reduce power consumption
a lot more.
Plus the pump then usually
costs less and
takes up less space and, again,
uses less power. Bonuses across the board!
