ro/di filter help

[gannmann9876]

i have a aquasafe rodi 100 gpd unit that goes thru di medi about every three months. i flush the membrane every so often. i just replaced the di media about two weeks ago and it is already bad i have ordered a new membrane. my water out of the tap is 190tds. i was wondering if i am on the right track with the new membrane and what order do the filters go in the sediment carbon ect. when i bought the unit it came in a box not assembled. help me please it is costing me a small fortune in di media and a constant battle with algae bloom.

 

[sandalscout]

Wow, yeah, something's not right.... How many stages do you have?

I'm definetely not a water expert, but my 4 stage is:

1 Micron Poly Filter ->
.6 Micron Carbon Block ->
DI Resin ->
RO Membrane

I might have the RO and DI stages backwards, but my tap is about 115 TDS PPM, and I replace my filters MAYBE once every 12 months, and I'm on my first (I think) membrane after more than 16 months.

 

[MVlk]

Not an expert either, but I am confident the DI goes last. I agree there seems to be something off with your rate of replacement needed. Sorry but no immediate answers.

 

[Sir Knight]

The correct order is

1) sediment
2) carbon
3) RO
4) DI

Joe

 

[gannmann9876]

it is a five stage filter

 

[luckyfish]

Follow Joe's order. If it is 5 stage then you probably have a 5 (or 1) micron sediment then a 1 (or .5) micron or an aditional carbon block. Make sure you are running in the right order.
Where are you buying your resin?
Are you packing it down in your DI resinn when you relace it?
How much water are you making in before changing? 190tds is not terrible to start with so you should get over 100 gal of RO/DI before needing to change.

 

[gannmann9876]

i may get 30 gallons maybe i have been using the media that came with it but i just ordered some from h20 solution or something like that i found them on ebay i packed the media down more than i normal a friend told me my membrane could be bad so i ordered a new on i figured all new filters should do the trick. i have changed all the filters once before (except the membrane) but i have not had it much longer than a year

 

[NeveSSL]

If you're DI is going fast and its in the proper order, your membrane is shot.

Brandon

 

[sandalscout]

Yeah, sorry, I thought I might have that backwards. What do your sediment filters look like after 6 months of use? Mine just barely show signs of yellowing.

Are you making a bunch of really small batches of water (1 or 2 gallons at a time) or larger ones? I use 35 gallon storage cans, so I usually make 20-30 gallons at a go. Cycling frequently is not real good for membranes.

 

[gannmann9876]

i have a 4 gallon tank that came with it so maybe i need to get a bigger resivor

 

[gannmann9876]

i changed all the filters i had the carbon filters backwards. the membrane had black stuff on the llid and the top of the membrane. there was also a salty type crust in the membrane housing that i had to scrape off. out of the tap is only 135 when i tested it yesterday got a 2 on the first batch now its down to 0. maybe it was the membrane or filters being out of order changed everything maybe it will last longer than last time thanks for the help guys

 

[andywe]

Glad you got it worked out ganman!!

 

[Buckeye Hydro]

If you can provide a bit more information we can help you.

1. What is the water pressure at the membrane. I believe what you have is an ebay system that comes w/o a pressure gauge, right?

2. What is your tds reading in the following 3 locations:
Tap? - you reported 135 ppm
RO (not DI)?
DI?

3. What is your waste water to purified water ratio? To figure this out, line up about 8 identical glasses in front of the system. With your waste water tube in one hand an the DI out tube in the other hand, how many glasses of waste water do you produce in the time it takes you to fill up one cup of DI water?

4. Does your system have a horizontal or vertical DI stage?

You should not have had any sort of "crust" at all in the ro membrane housing. Whatever you saw on the inside surface of the housing also likely could be found inside the membrane - which is not good.

Russ

 

[gannmann9876]

the system i have is aquasafe it was a bad deal on ebay it came with the pressure gauge just not enough fittings to hook it up the di stage didnt come with it so it is from h2o science and is vertical. i replaced all the filters in the entire unit. when i got the unit in it was in a box not assembled and the membrane was just lying there not wrapped in anything. i didnt have any instructions. a friend said he could help but told me the reverse order of the filters so i ran it backwards for a while. maybe all this could be the problem. what should the pressure be at the unit?

 

[Buckeye Hydro]

The gauge should read the pressure in the tube that runs from the last prefilter to the "in" port on the membrane housing.