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#### Ben Brewcat

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I'm going to begin collecting rain water this spring (I'm aware of all the caveats). I'd like to use an inline pump to run the water to a regular handheld watering wand/breaker. How many GPH are needed for a reasonable flow, using garden hose? There'll be little to no vertical gain, just a modest horizontal movement through a short run of hose, maybe 20 feet. Could I just measure the flow on my city water and then get a pump with comparable flow? It need not be self-priming BTW.

Anyone have a setup/experiences to share?

#### Swobee

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Do you have a way to connect the wand to a standard garden hose from your home or shop sill ****? Is so, time how long it takes to fill a 5 gal bucket and that will be the approx GPM output from the wand nozzel. Add some extra to cover friction loss through the hose and that should get you pretty close to the pump size you need. I can't imagine those wands putting out much water, but have never timed any that we own. A shower head today typically puts out 2.5 GPM or less and the wands aren't flow restricted, so they could easily be more than that. Just a stab. I guess another answer could come from a question - how many GPM do you need? Remember also every foot of vertical rise reduces the pump's output capacity. Our backyard pond pump puts out 4100 GPH at 0' vertical lift, but about 2/3 that at 5' vertical and almost nothing over 10'.

#### Ben Brewcat

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I don't really know how many GPM I need. I guess the slower the flow the longer I stand at each pot . At an estimate, I prolly put about two or four gallons in the larger ones like the banana tree lugging the watering can. Good idea on measuring what the wand puts out under city pressure.

Anyone know what GPM pump it takes to generate comparable pressure to municipal?

#### odfrank

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You don't need much pressure, you just need the desired GPM. Make sure whatever pump you use can take the back pressure when the wand is off. You city water probably flows at least 15GPM which is more than you need to water some plants indoors.

#### drobbins

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I think when go shopping for a pump any descent one will come with a chart that gives you the expected flow rate given such things as head and length of run of pipe. they ought to give you that info before you buy it so you can make the right choice. if you were pulling from a pond or a stream I'd get a shallow well pump

but for the amount of rainwater you are going to collect that would probably be overkill. how are you going to collect it? off your roof?

my dad had a stream in his backyard and we put in a shallow well pump, he had the greenest yard in his neighborhood
he tried those pumps they make for koi ponds but they never held up

Dave

#### giant pumpkin peep

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I had a water tank for rain this past summer. I have a 250-ish gph pump. Twice more power would have been nice.

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#### kwest

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i would get a pump that would put out at least 4-5 gpm. which is about 300gph. make sure that your pump puts out this 4-5 gpm at 30+ psi or 60+ tdh. the 60+ tdh is equal to 60+ feet of elevation. you will want a pump that puts out both volume and pressure if you want any spray at all. it will also need to overcome the friction loss of the hose. i own a well drilling and pump business so if you have more questions let me know. a pump like drobbins posted about would work fine it is of course a pretty low end pump but it should work for what your doing. you may just want think about getting a cheap sump pump if you are more interested in volume than pressure. it would be much simpler to use and install.

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