RO/DI question

[Myka]

Originally Posted by Treebeard

I will try to supply a picture when I go home for lunch.
I have the order exactly as you stated below. It is possible that I exhausted the DI resin because I did not change the membrane at the same time I changed the resin and particulate filters, but the guy from Aquasafe said the membrane should last for 12-24 months.

I will also test the raw water and the water after the membrane.
It is a 7 stage filter, if I understand correctly. There are three canister filters, followed by the RO membrane, followed by three DI canisters.
I agree with your comments on this adjustable flow restrictor. It is a real pita to set correctly. What kind of system are you using?

I have an AquaFX Barracuda 4 stage was $180 I think. Your first three cartridges (I'm assuming one particulate and two carbons?) should be changed every 6 months no matter what. The RO should last the longest, but it's hard to pinpoint how long it will last. Be sure when you do replace it that you replace the first three just before replacing the RO. The DIs will last varying amounts of time as well given how much TDS is reaching them. Measure the TDS of the water after the RO but before the DIs as I described above, and the tap water, and we can go from there.

[hillegom]

When you change your particle and carbon filters, disconnect the feed line to the RO.
After the filters are changed, flush water through and catch the effluent. A lot of times, the water will have small particles of carbon "dust" that could screw up the RO membrane and/or the flow restrictor. When the effluent, is clear, shut off the water and reconnect the line to your RO. Possibly, you have some small particles stuck where they should not be

[hillegom]

Forgot to mention, if you have an incoming TDI of 50, a reading of 0 output is easily attainable.

[Myka]

Originally Posted by hillegom

When you change your particle and carbon filters, disconnect the feed line to the RO.
After the filters are changed, flush water through and catch the effluent. A lot of times, the water will have small particles of carbon "dust" that could screw up the RO membrane and/or the flow restrictor. When the effluent, is clear, shut off the water and reconnect the line to your RO. Possibly, you have some small particles stuck where they should not be

What he said. I should have mentioned that...sorry.

[Treebeard]

Apparently my memory is not what it once was, or maybe it never was....anyways my raw water is 276. TDS after the RO membrane is 20.
I did not have time to take a picture, but from the instructions it is a 5 stage system:

1. 5 micron sediment
2. Carbon
3. 5 micron coconut carbon
4. RO membrane
5. DI cartridges (3)

At the beginning it was reducing TDS to 0.
When I changed the carbon and sediment filters, and the DI resin, I did not change the RO membrane, nor did I disconnect and flush the filters.

Is my RP membrane ruined, or can I flush it out? As I said previously, I am also having trouble with the flow restrictor so I guess it is also screwed up. Your explanations would explain the problem.

[mark]

Have the Aqua-safe also.

With a TDS of 20 after the RO would say it's okay but your DI is probably exhausted.

If your still running the post carbon after the DI, it could be the cause of the TDS not zero. Do you have the bladder, because if that wasn't drained, might be a cause also.

Diagram here

[hillegom]

For an aquarium, your DI should be your last filter, For your drinking water, preferences vary, but I have a charcoal as the last filter for the fridge and at the sink tap

[Myka]

I have no idea what the coconut carbon filter is...???

I may have missed it, but how many GPD is your system rated for? Most RO membranes (Filmtek 50 & 75 gpd and BFS 150 gpd) are 98% efficient which means if the water going in is 100 ppm TDS the water coming out will be 2 ppm TDS when it is new, and that will slowly rise until you need to change it. The Filmtek 100 gpd membranes are only 90% efficient, so if you have the Filmtek 100 gpd this is probably not a good choice for your higher TDS source water. You should be able to replace your flow restrictor with a regular type...they are cheap. Then choose a compatible RO membrane. I would suggest either the 75 gpd or the 150 gpd if you really want, just make sure it is 98% efficient. I think you may have exhausted your DI resins, but you can replace your RO membrane, and figure that out later. Don't forget to replace the sediment and carbon filters before the RO, and flush them before hooking into the RO like described earlier. I would ditch the coconut filter...don't know what's up with that, sounds weird.