Water Filter Placement.......

[ehenry]

All, I'm in the process of plumbing my "off the grid" little camp house. I"m catching rain water in a 300 gallon cage tank, I have no intention of drinking the water, just washing dishes, flushing a toilet and a shower. I'm using a 110v shurflo pump that cuts off at 55 pounds of pressure and I'm wondering where the best place for the filter would be....on the tank side of the pump or the pressure side of the pump?

 

[foodfisher]

Tank side to protect the pump, pressure side to protect the outlets.

 

[Boomyal]

That ShureFlow pump will not produce enough suction to have a small micron filter between the reservoir and the pump. Put the filter after the pump.

 

[ehenry]

Its a 30 micron whole house.. The spec sheet on the pump says it will lift and prime from 9 feet if that matters.

Forgive this question, but when they talk about "Total Head (ft.)" are they talking about how far the pump will push the water? This pumps total head is 100 ft.

 

[Boomyal]

Its a 30 micron whole house.. The spec sheet on the pump says it will lift and prime from 9 feet if that matters.

Forgive this question, but when they talk about "Total Head (ft.)" are they talking about how far the pump will push the water? This pumps total head is 100 ft.

If I am not mistaken that Shureflow pump is a diaphragm pump, not a positive displacement pump. Of course it has to be able to SUCK some or it would only work in a flooded suction mode. Any cartridge filter will have some resistance to it and at the least it would cut down on the lift and prime height. I also question your choice of a 30 micron cartridge. You would be better of if you used a lower resistance 100 mesh strainer (149 micron) on the suction side of the pump.

http://www.homedepot.com/p/Unbranded...-100/203449591

Whereas your rain water reservoir may accumulate some debris, it would most likely be of a size that would settle out. You should not be pulling your water off the very bottom of the tank, anyway.. It is unlikely that you would have much, if any, smaller, suspended particles in the 30 micron size, in the rain water. Even if you did, you should use a 5 micron cartridge on the pressure side.

....and yes, the 'total head' is how far up the pump will push the water.

 

[ehenry]

Here is what I did. I placed the filter on the suction side of the pump and also put a screen similar to what Boom listed before the filter. I placed the filter and screen below the water level in my tank so the filter fills up via gravity and the pump has no problem priming and reaching cut off pressure. Now we will see how long the little pump lasts.

 

[Boomyal]

Here is what I did. I placed the filter on the suction side of the pump and also put a screen similar to what Boom listed before the filter. I placed the filter and screen below the water level in my tank so the filter fills up via gravity and the pump has no problem priming and reaching cut off pressure. Now we will see how long the little pump lasts.

Well that will work until the mesh strainer or cartdridge filter become loaded up, then your pump will just cavitate. For the long term you would have been better off leaving the mesh strainer in its flooded position and installing the filter (5 micron) on the pressure side of the pump. You are not going to get any particles through that strainer that are big enough to hurt your pump but you could get particles that can pass through a 30 micron filter that you do not want in the facility. That pump will be more adept at pushing that it will be at sucking.

 

[mla2ofus]

Even tho you don't drink it a little bleach in the tank occasionally won't hurt as rain water off a roof will have all kinds of organic stuff in it.
Mike

 

[Boomyal]

Even tho you don't drink it a little bleach in the tank occasionally won't hurt as rain water off a roof will have all kinds of organic stuff in it.
Mike

Good advice! One gallon of the old 4% sodium hypochloride household bleach will treat 52,000 gallons of water to 1 ppm. That is the minimum level to kill any bacteria, along with about 30 minutes of contact time. In recent years, chlorine suppliers got tired of paying for the shipping of water so the reduced the total volume to about 3 qts but increased the concentration of chlorine into the 6+ range.

You do the math. When you are dealing with a couple of hundred gallons it does not take too many tablespoons of the current 6+% chlorine to give you the 1 part per million. At that level you will barely notice it in your water. Much higher than that, you will think you are in a public bath.