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btuck887
01-03-2014, 06:58 PM
Picked up a second hand spectra pure 90 GDP rodi unit. Set it up and am getting a ration of 7:1 which is way to high. Is there any place in the city that carried flow restrictions? Theinstructions say u want a 4:1 ration but at 7:1 will u still get "good" water? Also where in the city can I pick up cheap filter replacements?

Thanks

Magickiwi
01-03-2014, 07:11 PM
That's a high rejection rate. I think you need to shorten the flow restrictor. Check the manufactures website, they have manuals for all their units online.

btuck887
01-03-2014, 07:55 PM
Wouldn't I need. Longer flow restrictor to restrict more of the waste water?

btuck887
01-16-2014, 04:37 PM
One more question regarding rodi units. I set up the unit and it's producing 2-3 ppm water which I'm fine with but what other tests do I need to do on the water before I know it's safe for the tank? Or is a tds meter test all I need to do?

Thanks in advance

ronau
01-16-2014, 04:45 PM
How old was the unit? Membranes can be permanently damaged if they let it dry out. I think Home Depot or any other reno store is the cheapest for sediment and carbon filters. Not sure what other tests you could do on RO water. I think that is why RO/DI is preferred, water is stripped down as practically possible.

btuck887
01-16-2014, 04:50 PM
How old was the unit? Membranes can be permanently damaged if they let it dry out. I think Home Depot or any other reno store is the cheapest for sediment and carbon filters. Not sure what other tests you could do on RO water. I think that is why RO/DI is preferred, water is stripped down as practically possible.


I picked it up used and it still had water in it when I got it so I'm assuming they had just takin it down. It is an rodi unit so with it producing water with 2 -3 ppm I shouldn't have to do any other test on the water and it should be ok to use for mixing salt? I have never used one before so I'm just a little worried about putting the water in the tank without asking some questions first ha ha

reefwars
01-16-2014, 04:53 PM
Have the cartridges been replaced when you got it

btuck887
01-16-2014, 05:02 PM
Have the cartridges been replaced when you got it


No he said they were replaced fairly recently, he said the resin should be changed as most if it has changed color. But if it's coming out at 3ppm doesn't that mean to resin is still ok, or should u change it before the Ppm goes up?

reefwars
01-16-2014, 05:05 PM
For cheap as they are I would replace all three And get a fresh start

btuck887
01-16-2014, 05:07 PM
For cheap as they are I would replace all three And get a fresh start

Where in town would be the best place to pick them up from?

reefwars
01-16-2014, 05:11 PM
Concept has them all same with alot of water stores:)

ronau
01-16-2014, 05:16 PM
If it is a RO/DI, it should be producing 0 ppm water. With only 2 - 3 ppm, I would guess your DI resin is spent. Replace it for ~$18 and you should be good to go

btuck887
01-16-2014, 05:17 PM
Concept has them all same with alot of water stores:)



Thanks :biggrin:

btuck887
01-16-2014, 05:38 PM
Lastly does anyone know who would carry flow restrictors? The ration I'm getting is 7:1 which is way to high

Abe
01-16-2014, 10:30 PM
J and L has the flow restrictors. Also you can use a shut off valve on the drain side to control the flow until you find a restrictor.