Anjon Manufacturing Monsoon 4000 GPH Pond Pump – MS-4000

Original price was: $346.00.Current price is: $259.50.

Model Number – MS4000
Max Pump Flow – 4,000 GPH
Max Head Height – 21″
Discharge Outlet – 1.5″
Intake Outlet – 1.5″
Pipe Diameter – 2″
Volts/Watts – 120/276
Dimensions – 9″x7″x7″
Weight – 18 lbs
Cord Length – 30′

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The unique design of the Anjon Monsoon Asynchronous series makes it an ideal choice for fountains, waterfalls, and smaller ponds. An energy-efficient electromagnet is sealed in an epoxy-filled housing. The drive shaft and electromagnetic rotor are recessed in the motor housing: near silent operation and extremely low operating cost.The high flow, energy-efficient hybrid drive technology combines the high flow characteristics of a direct drive pump with the energy-saving efficiency of a mag drive pump. The intake screen prevents clogging while passing solids up to 0.25 inches. The asynchronous drive motor can be controlled with a variable speed controller (not included) that permits you to increase or decrease pump flow as needed. Impeller passes solids up to 0.25”. Engineered for 24-hour continuous use, overload sensor prevents burnout. Contains no oil, completely safe for fish, wildlife and aquatic plants.

Note: The speed controller does NOT work with the MS8000, MS10000, MS12500, MS3000100, MS5200100, MS6100100, MS80001000, MS10000100, MS8000200, MS12500200 & MS15000200.


Pond type, head height, and friction loss all factor into the minimum pump size requirements.
Pond Type:
Water Garden, Few Small Goldfish: Circulate total pond water volume every 2 hours. Example: 2,000 GPH pump for 3000-gallon pond with 2" waterfall.
Fish Pond, Several Small Fish: Circulate total pond water volume every 1 hour. Example: 3,800 GPH pump for 3000-gallon pond with 2" waterfall.
Koi Pond, Several Large Fish: Circulate total pond water volume every 3/4 of an hour. Example: 5,500 GPH pump for 3000-gallon pond with 2" waterfall.
Head Height:
To calculate the head height, take the vertical height of your waterfall; the distance between where your pump is (typically in the skimmer) and where your waterfall is, and adding the static head pressure (pipe and fittings) 1′ for every 10" of tubing and 1′ for every elbow or "T" fitting.
Example: 3′ (vertical height) + 2.5 (25′ of tubing) + 2′ (for 2 elbows) = 7.5′ of Dynamic Head Pressure
Note: Head height is important to take into consideration due to the laws of fluid dynamics. Please refer to the flow chart above to help choose the correct pump.


When Sizing your Freeze Flex Pond Hose, make sure you choose a pipe that will not restrict the flow of your pump! If your hose is 1.5" and you buy a 6,000 GPH pump, your pipe will only allow 4,400 GPH to pass through it. You will be wasting money on electricity and paying for a stronger pump that will not give you the desired result. You will need to run an additional pipe or change your hose to get the desired flow rate! Many people expect to achieve greater flow by simply buying a larger pump. They do not realize that flow will not increase unless the tubing can also support this increase inflow. Please do not let this happen to you. Using the chart above, you will be able to easily determine the best size tubing for your pump size. Do not use pumps on an extension cord. They must be run on a dedicated 15 Amp GFI circuit.


Rectangular Ponds
Length x Width x Average Depth x 7.48 = Gallons
Example: A rectangular pond that is 15’ long, 10’ wide and 1.5’ deep is… 15’ x 10’ x 1.5’ x 7.48 = 1683 Gallons
Oval Ponds
Length x Width x Average Depth x 0.8 x 7.48 = Gallons
Example: An oval pond that is 15′ long, 10′ wide, and 1.5′ deep is… 15′ x 10′ x 1.5′ x .08 x 7.48 = 1346 Gallons
Round Ponds
Radius x Radius x Average Depth x 3.14 x 7.48 =Gallons
Example: A round pond that has a 12′ diameter and is 1.5′ deep is… 6′ x 6′ x 3.14 x 1.5′ x 7.48 = 1268 Gallons
Length x Width x 0.25 x 7.48 =Gallons
Example: A stream that is 20′ long, 3′ wide, and 3" deep is… 20′ x 3′ x 0.25 x 7.48 = 112 Gallons

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