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R/O Unit Problems

So I got a spiffy new (and expensive) r/o filter because I was sick of having to buy cases and cases of distilled water from the grocery store. The filter worked fine for like.. a day. It gave me a little bit of water and some leaks sprouted, so I fixed the leaks. Then I checked a few days later and the TDS had gone from 7 to 53 and currently it has been fluctuating between 132 and 60 (132 is HIGHER than the TDS of the water without being filtered) so I contacted the tech support from the place that I bought it and they've been next to useless. They rarely ever even reply to my emails now and I'm getting pretty frustrated since I've had to give my CPs water with 60+ppm water. So those who are experts with r/o units.. please HELP!!!
If it's leaking, take it back. That's ridiculous. Since they had bad customer service, request a refund and not a replacement.
Chrono, have you got a pressure gauge,

the best way to troubleshoot one is to just get all your measurements and go from there, its one of those Occam's Razor thangs LOL

most critical is the pressure at the membrane inlet with the outlet at full flow

and can you determine your brine ratio and rejection ratio as well?

curious as to why TDS would be higher on the output, I know this is a no brainer but are you possibly using the waste water output instead of the permeate output?

sorry, but i had to ask


ref this previous thread
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sounds like it's not hooked up correctly.
how much did you pay for it?
Is it the typical 3 pre filters and a r/o filter?
maybe you could show a pic of how it's hooked up?
Who did you purchase from? ROs rarely leak sounds like incorrect hook ups.
I have no idea how to get the rejection ratio.. I'm not using the waste water output, I know that (but I did double check. :p) Everything on the membrane case came pre-attached.. so I don't think I messed anything up there.

I do have a pressure gauge, but I don't know how to use it.. do I just.. unhook a connection and place the tube inside the gauge?

In order to get the brine ratio, I'd have to unhook the waste line from the faucet and measure how much comes out when I flush the system, right? Then I have to compare that to the amount of water that goes to the tank. Oi.. this stuff isn't easy.

I'll get those measurements ASAP I won't be able to get them right now though.

Why do I have a feeling that this is because my step dad (who helped me install the r/o unit together) didn't follow the (horrible) directions?

Edit: This is the one I got... http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=150132876304&ssPageName=STRK:MEWN:IT&ih=005

I will get a pic when I take the required measurements. The leaks that I had were just because I needed some teflon tape (my step dad actually used silicon) on the threads for the elbows and junk. There was one on the output from the DI filter and one on the tank.

Also, I can't send it back. They only have a 3 day replacement offer. I don't even think I had it connected within three days of getting it.
Three day replacement? That's ridiculous and if you would have said that's as long as they'll accept returns, I would have told you that's a big clue on the quality of the product.
Who's the maker of your TDS meter? The brand I bought had huge problems (3 duds in a row). Water would keep getting sucked into the electrode and giving me false readings. Instead of 4, it would say 80, then 130, then 30, etc. I had to take the meter to another unit to verify the same behavior.

Also if you use a bladder tank, the tank might need to be flushed. (Filled then emptied) Most of these tanks are for just normal water and might have dust and things like that from manufacturing, they are not made in a clean room or anything fancy. If you have a tank, it might have a cutoff valve, turn it off let the filter run and look at the reading coming out. If it's more normal then you know that'd the part that needs to be flushed. Also let the filter run for a while, take a reading every 15 mins and see if it's getting lower. If that's the case, then your system probably needs to run for like an hour to get it down to it's normal level.

Mine leaked too, one fitting needed to be tightened and the canisters needed an extra umph to get a good seal going. But I've been very happy with mine once it got into a normal working habit.

Just looked at your ebay pic. Remove the taste and oder filter. Or tee off before that filter. It's just some weird coconut husk thing. But it can add other things back into the water. I have mine tee'd off for the plants, but still use it for the sink that I drink from.
  • #10
oh my "silicon"... ewwww im hoping it was before the prefilters and he was careful enough to skip the first few threads and use it sparingly

but the rejection ratio is easy... take the inlet off of the membrane and measure the TDS, then take the outlet off the membrane and measure its TDS

if it is going up we have isolated the problem, (assuming pressure is adaquate)

but no more silicon please.... it can damage the membrane (people tend to use too much)

to properly take pressure measurements you need to "tee" the gauge in, a deadhead pressure (like you implied) is useless, we need "dynamic" pressure readings
  • #11
Chrono, its a good basic unit, nothing wrong with the make of it

same one many here use, myself included

flytraps advice about flushing is a good ideal, i do mine weekly
  • #12
Same here Chrono, I bought a very similar unit and it does a really good job. Just needs some fine tuning. 8)
  • #13
notice how the gauge is installed in mine for routine monitoring of inlet pressure(we may need to check yours in a diff spots but you get the idea)

  • #14
I flushed it for like 2 days straight because I forgot it was on.. and before that, very often. When I flush it though.. it sounds like a lot of water was kept under pressure there, it starts squirting into the pipe, I can hear it.

As for the silicon.. I know it's not that problem because the high TDS happened BEFORE the silicon was added.. I knew we should've just sticked to the teflon tape...

I also did fill and empty the tank a few times before I used it. I think I did it like 3 times. That final filter is supposed to take care of that stuff though. I'll take some TDS readings after every filter (after the prefilters and one before) so to try and isolate the problem.

I gotta get offline for now though.. I'll get what I need then I'll be back!

Edit: What is that brown water in the picture? Mine doesn't have one of those...

Just took another TDS reading, I got 172..... wtf

Also, my TDS meter is made by Milwaukee. This one.. to be exact..
  • #15
Sweet you got a permiate pump as well, how do you like it? I have to get a 90% valve yet though.
  • #16
love it!!!!

best upgrade their is, recycle times are a lot better, filter life is a lot longer and a whole lot less waste water

a must have if you use a bladder tank

brown water???.... ohhh you must mean the mixed bed for demineralization, depends on which system you buy.... most probably wont have it, its actually little beads that turn tan as they get used up
  • #17
Av8tor1, I love the clicking noise it makes and bouncing tubes from the pressure. It always scares my roommates when they are downstairs doing laundry.

Chrono, find out what kind of TDS meter you have. If it's one with two probes, switch the probes. You should get the same readings, if they are different you have a bad meter.


::Edit::, oops didn't see the link you posted. Should have read closer. Not really familiar with that type of meter. 8(

The final filter is for taste and oder....
"Granular activated charcoal is made from raw materials (such as coconut shells or coal) that are high in carbon. Heat is used to increase (activate) the surface area of the carbon; this is why these filters are sometimes referred to as “charcoal” filters. The activated carbon removes certain chemicals that are dissolved in water passing through a filter containing GAC by trapping the chemical in the GAC. However, other chemicals, like sodium or nitrate, are not attracted to the carbon and are not removed"

I talked about this filter with a Reef Expert and he always recommends removing these. Your other filters do all the work, it's like putting a duct tape racing stripe on a brand new car. 8) Plus these filters can add ppm elements back into the water. This filter is for us, and for the ebay guys to say "hey! you have an extra filter than this other guy."
  • #18

I assume you will be buying a couple gallons of distilled water tonight, when you do check it with the same TDS meter to verify it is reading correctly, store bought distilled water should be test out very low if anything... good "shade tree" verification of your meter

and you can flush too much, think about it... that flush water is still going through your sediment and charcoal prefiltration stages, so you are using up your ability to remove chlorine with every flush, and it definitely will damage the membrane if it isn't removed

just flush once a week or so, and then only for a few mins... 10-15 at the most IMHO, if you need more flushing then that you are treating the symptom of a problem and not it's root cause

Nate, ive always heard that as well... the part about the taste, but from articles that i have read it is really there to remove any VOC's that are gassed off by the bladder, you know that funky taste water gets from a plastic canteen after a while... ewwww, but it could be just for looks too LOL

of course im not an expert by any means and ymmv
  • #19
Starting TDS: 125-170
TDS after Prefilters: 200
TDS after Membrane: 56
TDS after RO/DI filter: 120 (It was 66 when I checked a few hours later)
TDS after carbon filter: (about the same as for the RO/DI filter)

Brine: It took 35 seconds to fill an 8oz cup (245ppm)
RO: It took 5 minutes to fill an 8oz cup

I didn't get the tee yet for the PSI gauge yet since I haven't been able to get down there yet.. also.. I'm not really sure which one I need. Just a three way compression tee? The pressure as far as I know, isn't much. I run off a well and kind of expected that it'd be low. Water trickles out of the tubes after the membrane.. maybe about 2 drops a second. Not sure if that would affect the TDS levels though.
  • #20

ill be honest, your numbers are pretty strange... TDS shouldnt be going up after prefiltering, should be lower if anything... i would look at the last prefilter element to see if anything appears wrong... maybe it is leeching carbon?

based upon your membrane output you would have about a 75% rejection ratio, which could indicate a possible low pressure problem

but that isnt your main prob at the moment,

open the final prefilter and have a look... do you see a bunch of carbon laying around in it, if so rinse and reinstall and recheck tds after prefiltering stage

and the fittings are called hmmm something like "john cleese" LOL , i get mine at lowes, but they are not compression fittings

and your brine ratio seems terrible, how did you adjust the variable flow restrictor?.... however it was done it needs to be around 3:1 (3 cups brine to one cup of permeate (RO/DI output)... if you dont have enough restriction this can cause a low pressure condition at the membrane.., and too much restriction can damage the membrane

but we got more then one issue it seems, one step at a time... check that final prefilter element, lets find the increasing TDS prob first, get your tee and then we can check pressures

(additional ref material, just found spectrapure's factory troubleshooting tek download here)

unless they went to a diff style, here is the tee