So, I have a 50 GPD RO/DI unit that is just the inline type, not canister (uses refrigerator type inline cartridges). I ordered a new sediment, carbon and RO filter off of ebay the other day (separately) and installed. However, my flow into my RO/DI storage container was then very slow and the TDS coming out of the RO into the DI resin is ~36ppm, which seems very high as it has been 9 ppm in the past. Now, last night after taking things apart and re-fitting everything I am getting almost 0 flow. Any ideas or suggestions? I'm about to just junk the cheap thing and go with a 75 gpd canister system if I can't get this figured out. Thanks in advance!!
Any ideas on an RO/DI issue?
- Thread starter knapp870
- Start date
BLADEYAMAHA
Well-Known Member
I'm not sure, can you post pics, are you putting it together correctly? Not trying to piss you off, just trying to hit the basics. Uh, are the cartridges in correctly? Reversed? In order? Maybe get a Canister style one if you don't get it going. Not sure without being, don't know what else to say. What brand is it? Model?
Having pure water is paramount to running a good system and is a staple when trouble shooting problems. I would look for a unit and be done with it. BRS has some good ones but at the end of the day most units are good and it all depends on what you put in them so if you find a used one cheap, buy it and replace all the filters.
I have the BRS 5 stage RO/DI plus and I am very happy with it.
I have the BRS 5 stage RO/DI plus and I am very happy with it.
BLADEYAMAHA
Well-Known Member
Well one thing is the RO filter does not start filtering low ppm right off the bat, it takes about 5 or 10 gallons to run through it before it starts getting the low ppm numbers.
BLADEYAMAHA
Well-Known Member
You throw the first 5 or 10 gallons out. You do want near 0 ppm output.
BLADEYAMAHA
Well-Known Member
Ah, go to Saltwater and Reef Aquarium Supplies - Bulk Reef Supply and get a good one, don't know what else to say.
Bulk Reverse Osmosis Filters & Systems - Bulk Reef Supply
Bulk Reverse Osmosis Filters & Systems - Bulk Reef Supply
Been working great for over a year, I don't see why it isn't a "good" enough one. 0 ppm is 0 ppm in my book. It is essentially BRS 3 Stage Space Saver RO System - 75GPD - Reverse Osmosis Systems - Bulk Reverse Osmosis Filters & Systems - Bulk Reef Supply except 50 GPD.
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BLADEYAMAHA
Well-Known Member
I thought it wasn't working good.
BLADEYAMAHA
Well-Known Member
Oh the style would be fine, yeah, you can get another one like it, just not the standard though, replacement filters for the 10 inch canisters are more common and more readily available.
BLADEYAMAHA
Well-Known Member
Man, maybe crappy filters. IDK.
Well I troubleshot this issue for awhile last night and finally found that the stoppage was in the last fitting coming out of the DI resin. A little twist and it began to flow correctly. However, I am still getting like 19-22 ppm out of the RO membrane 
I feel like this will cause me to run through DI resin pretty quickly.
I feel like this will cause me to run through DI resin pretty quickly.
Willie McDaries
Well-Known Member
Well I troubleshot this issue for awhile last night and finally found that the stoppage was in the last fitting coming out of the DI resin. A little twist and it began to flow correctly. However, I am still getting like 19-22 ppm out of the RO membrane
the sediment and carbon filters are there to remove sediment and chlorine,which will destroy the RO membrane,most Ro membranes remove about 90%..for instance,if you have 200TDS coming in,the RO will have very nearly 20TDS coming out of it...my TDS coming into my house are around 160TDS,my RO output measures about 16 TDS....test the water coming in to the sediment filter,if it is around 190 to 200TDS,it is working as it should and you are fine,the DI will remove the rest