Method to Estimate Gallons per Hour for Old Pond Pump

[BSquared18]

Hello. The snow has melted here in Minneapolis, and I’m ready to get our backyard pond working. Our Pondmaster 4800 pump has been producing the pond’s waterfall for about twelve years (about five or six months per year here in Minneapolis). It seems to my wife and me that the flow may be getting weaker.

Before taking the pump apart to clean it and buy a new pump if that doesn’t work, I wanted to determine as best I could what the current flow is and compare the performance with the manufacturer’s published figures. The steps I’m considering are:

-- Drain the pond and install the pump.

-- Fill the pond to the desired depth.

-- Estimate the vertical height between the pond’s water level and the output hose at the top of the waterfall.

-- Have a way to capture the water as it comes out of the water-return hose at the top of the falls. For example, use two quart bottles, emptying one while filling the other. Set a timer to notify when, say, two minutes have passed.

-- Keep track of the number of quarts of water measured in the two minutes.

-- Perhaps repeat the process a few times and average the totals.

-- Then, do the calculations to convert the number of quarts in two minutes to number of gallons in an hour.

Please let me know if this method makes sense and/or is there an easier way to measure the gallons per hour flow at the height the water is pumped to?

Bill

 

[Bluerooster]

At 0 head it should flow 5100 gph. Or 85 gpm. So I would suspect you would need a larger measuring container. Here's a chart for several models of pondmaster pumps.

 

[BSquared18]

Good point. Trying to measure 85 gpm with quart bottles won't work. Unless, because the pump is old and hasn't been serviced, the flow might be slower, which is what I want to find out. Trials to come.

Also, I will be measuring how many feet the outlet is above the water level, which, of course, will reduce the flow.

Thanks for the input. It gives me food for thought.

Bill