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wesbeene
06-21-2015, 09:59 PM
Hey guys,
Trying to get my RO/DI unit back up and running. Before i replace all the filters, i wanted to hook it up to a basement line and run some water thru it and measure in/out TDS. Problem is its been so long that i am not sure i have it hooked up correctly since my waste water valve is set to the closed position (and i am getting a light steady flow out of the waste tubing) but i am still not getting very much out of the membrane housing out flow. I remember that quite a bit of water like 75% is filtered to make 25% RO/DI water or less?? Anyone have any suggestions as to what to do to see if i am getting the flow i should? Thanks!

Wes

static reef
06-21-2015, 10:25 PM
Somewhere around here i have a gauge that you can borrow that hooks up to the hose faucet outside and gives you a pressure reading. Most units provide 1 g of good water to 3.75 g of waste. You can also buy a gauge to hook up to your rodi "tap water in" line that will give your pressure reading from bulk reef supply. I have one of these as well that i would sell for 10 bucks.

Each rodi unit requires a different pressure for optimum output. You should be able to google this "optimum pressure," unless you already have the meter in your unit.

If your pressure is to low you can turn up your home water pressure to the desired amount (videos on youtube to teach you how to do this). There is also a booster pumo that you can buy on bulk reef supply to boost your input to the rodi.

Not really sure about your question but i hope i answered it.

charleshardy5
06-22-2015, 09:04 AM
Two measuring cups... One for good water one for waste. I have mine producing 3:1 waste to good. I just ran my waste and good lines into the measuring cups and turned back the gate valve on my waste line until I got rhe paper ratio of 3 cups bad one cup good

wesbeene
06-22-2015, 10:21 AM
Two measuring cups... One for good water one for waste. I have mine producing 3:1 waste to good. I just ran my waste and good lines into the measuring cups and turned back the gate valve on my waste line until I got rhe paper ratio of 3 cups bad one cup good

Thanks Charles/JJ,
I just have a flow restriction valve on the system to control the ratio and it seems that i am getting more of 10 cups to 1 cup ratio at the moment with the valve all the way closed. If i open the valve even a bit i get more like a 20 to 1 ratio. Maybe i just need to change out all the filters since they have been in there for over 5 years and havent been used at all. Maybe they are bad and causing poor flow?

charleshardy5
06-22-2015, 10:35 AM
Sounds like maybe the valve is bad? That's A Pretty Crazy ratio. .. that or the ro membrane is bad maybe

Levi
06-22-2015, 10:55 AM
Sounds like maybe the valve is bad? That's A Pretty Crazy ratio. .. that or the ro membrane is bad maybe

Sounds like not enough pressure and restriction for the GPD membrane, the restrictor builds pressure in the membrane reducing the ratio. Mine is hovering around 2/1 waste to good and when we move I will hook up the booster pump to get down to a 1/1 hopefully.

wesbeene
06-22-2015, 12:34 PM
Sounds like not enough pressure and restriction for the GPD membrane, the restrictor builds pressure in the membrane reducing the ratio. Mine is hovering around 2/1 waste to good and when we move I will hook up the booster pump to get down to a 1/1 hopefully.

Can a bad membrane reduce/restrict flow that much though?

Levi
06-22-2015, 01:00 PM
nothing to do with "bad", but a 50gpd membrane vs a 90gpd have different restriction requirements as well as input pressure. Spectrapure or BRS can help answer what add on items you should get with your given pressure input to make sure you can maximize the good water vs bad water ratio for your given setup.

Coral Xpressions
06-22-2015, 01:52 PM
I've noticed that yes, if you have a bad or clogged membrane then you will have significantly more waste than good water. Especially after the unit sitting dry for years you are definitely going to want to replace it. Until then any results are going to be insignificant. I can get you pretty dirt cheap rates on membranes and filters are always in stock.

Levi
06-22-2015, 02:14 PM
http://www.bulkreefsupply.com/video/view/howto-know-when-to-change-your-rodi-filters/

Good video that BRS did on when should you change your membranes. I agree with what everyone else has said that you should replace all of your membranes because the unit has sat so long. If after replacing you still have a ton of waste water (which I believe you will) then look into the pressure going in and the pressure being restricted. If you take the flow restrictor off or have one that isn't building enough back pressure you will have SIGNIFICANLY more waste than normal. I believe this is what is contributing most to the issue.

wesbeene
06-22-2015, 06:17 PM
I've noticed that yes, if you have a bad or clogged membrane then you will have significantly more waste than good water. Especially after the unit sitting dry for years you are definitely going to want to replace it. Until then any results are going to be insignificant. I can get you pretty dirt cheap rates on membranes and filters are always in stock.

I do need a membrane and coconut filter (3rd stage) and a new DI filter. Can you get those 3 for me? I have a 6th stage which is just a polishing stage that i took off, i dont think i need it for aquarium use?
Can you shoot me a PM with the total please? thanks!

Coral Xpressions
06-23-2015, 08:55 PM
Wtf, my response never posted. My inbox is full and phones being stupid. Shoot me a text and I can provide info. 2102757520

wesbeene
06-23-2015, 10:07 PM
Wtf, my response never posted. My inbox is full and phones being stupid. Shoot me a text and I can provide info. 2102757520

Text sent. Thanks!