Need pump advise. What pump will run a ro/di filter?

Fish · #1 10-17-2006, 07:44 PM

Hi guys and gals,

I'm sourceing everything I need to get back into the hobby, and was wondering if anyone has experience with rain barrel sump pumps. My plan is to save my ro/di waste water in a barrel and then use a pump inside the barrel to pass it through the filter one more time (just to reclaim a little more water for the tank - if possible).
At a bare minimum, it would be nice if I could thread a garden hose from the pump to a sprinkler on my lawn. This would let me use waste ro/di water and rainwater to water my grass instead of frinking water.
Hopefully, my return to reefing will be marked with a little less waste. ( :

What size/type of pump do I need for this job? 1/2 hp? 1 hp? Something that I can connect a garden hose to - I can easily get a garden-hose-to-fiter adapter for it.
Thanks for the help,

- Chad

Joe Reefer · #2 10-17-2006, 07:48 PM

I think your going to need a pump that can pressure up to about 55-60 psi. I know that there is booster pumps for people that have low water pressures.

How much water do you think your going to reclaim by doing this?

Fish · #3 10-17-2006, 08:12 PM

Thanks Lando,
I have checked some pump listings online and they don't really say what the psi rating is. It makes sense though that I would have to match the house pressure for the filter to work properly.

I think that it should be possible to go from "2 gallons waste for every 1 gallon used" to something closer to 1:1. Of course this may decrease the life expectancy of my filter cartridges too.
Just the benefit of not dumping my filter water down the drain but putting it to good use... I can see it saving thousands and thousands of gallons of water.

- Chad

Joe Reefer · #4 10-17-2006, 08:36 PM

Quote:

Originally Posted by Fish

Thanks Lando,
It makes sence though that I would have to match the house pressure for the filter to work properly.

- Chad

Thats what I was thinking. I have no idea where your going to find a pump for that kind of application. Maybe you can somehow have a recirc line from the waste water line back to the input line then you would still be at city pressure.

Delphinus · #5 10-17-2006, 08:37 PM

This is what I would do. I'd have the barrell collecting the discard water off the RO/DI with a garden variety sump pump. You should be able to pick one up at HD/Rona for $80-100. Probably even comes with a float valve. The pump just routes water to an outside rain collector barrell. Then install dripline irrigation style soaker hoses to whatever parts of the garden need water.

The problem with watering grass is you tend to need a large coverage area. A pump could run your sprinker but if the intent here is to be green, then really be green, you know what I mean? Let gravity do most of the work for you with the slow flow irrigation instead of using electricity to spread the water.

Those sump pumps are not something you'd want to run long term, but in this case it's (presumably) just lifting the water from one reservoir to another. Its duty cycle will be very small that way.

Delphinus · #6 10-17-2006, 08:42 PM

As far as recirculating the waste water back through the RO/DI, I thought I read somewhere on RC of people putting a RO/DI on the waste water of one, and even another RO/DI on the wastewater of that one. Of course, that seems kinda costly.

As far as a low flow high pressure pump, there are such things and should run you about $100-200. The key to this style of pump is low flow, but can run pressure to about 80psi or even up to 200psi. People who have dart frogs sometimes use this kind of pump to produce a fog through fog emitters (you need very high pressure to get a good fog, otherwise the water droplets are just too big). At one point I knew a part number of a 200psi pump that you could get a Western Pump for about $160 but I've since lost the info since I never really followed through on my foray into that hobby. If you needed I could try to look it up but I'm not sure if this is the style of pump you're looking for.

Fish · #7 10-17-2006, 08:59 PM

Thanks Tony. I am concious of my electrical consumption (eg, I'm going T5HO to save over halide), but I'm not quite a hippie ( :
I guess if I was really "green" this wouldn't be the best hobby for me. Mostly my issue is with water. I lived for a couple years in a country where the water wasn't drinkable and you had to use bottled water just to brush your teeth. I guess it kinda made an impression on me and I'm still amazed that we use drinking water to flush our toilets here.
I think that a pump that would allow me to push wastewater through a sprinkler would be a decent compromise.

- Chad

Delphinus · #8 10-17-2006, 10:04 PM

The only thing I can sort of think of about that is that I can see the reservoir getting pumped empty in a manner of minutes whereas we usually need to run a sprinkler for 20 minutes in an area to get your 1cm. I dunno, I just sorta envisioning this being an expensive proposition for you (a high flow high pressure pump must exist but I see it being pricey), but then again I could be way off base.

I think you don't have to be a hippie to appreciate those low volume dripper style irrigation systems, and you could feed that with a rain barrell filled with RO wastewater.

Then again I guess I'm just trying to influence you into doing what I was sort of one day hoping to do myself, so if you do come up with a different idea that's cool too.

Good luck with whatever you come up with, I'm sure there are some good ideas to be be found.

mr_alberta · #9 10-17-2006, 10:43 PM

I think a permeate pump would work for you. Then you don't have to worry about pumping water back through your R/O system again afterwards:

http://www.aquariumwaterfilters.com/...pshop&Itemid=6

Fish · #10 10-17-2006, 10:56 PM

??? wow. I've never seen one of those before - and I have no idea how that works

- Chad