@ what PPM do you change RO filters?

[West1]

I have a RO drinking system and I have it "T" off to my DI where I use for the hobby.

Currently I change carbon/sediment filters every 3 months or when the sediment is 100% dirty. DI gets replaced once I have 1ppm reading.

I feel I am changing RO filters more than needed.

At what PPM should I be replacing my drinking/RO filters?

 

[reeftivo]

do you flush your ro membrane regularly?

that will extend the life of the membrane and extend the life of the carbon block. especially if the source water has high tds

 

[West1]

I do not, I will start now. Thx
Between each filter replacement, I do sanitize the membranes/tubing.

 

[reeftivo]

I do not, I will start now. Thx
Between each filter replacement, I do sanitize the membranes/tubing.

that helps.

flushing is the best!

 

[West1]

that helps.

flushing is the best!

So you also change filters based on look? Is there no real number to replace at like we do with the DI?

 

[reeftivo]

sorry, i usually change my three once the DI resin turns from blackish/purple to amber (regardless if O tds). my sediment usually looks very clean (light in color) and carbon block is un-discernible so i just change it out.

I repack my DI resin and get the refills through BRS along with sediment and carbon block. I pack my DI super tight and can get a few months out of it. I back flush each change out right when i install the new carts. that helps clear the dust from the carbon block and any that collect on the membrane at start up. My tank is relatively small compared to larger systems so obviously i would get more out of my RO than those with bigger tanks. it just works for me

 

[West1]

sorry, i usually change my three once the DI resin turns from blackish/purple to amber (regardless if O tds). my sediment usually looks very clean (light in color) and carbon block is un-discernible so i just change it out.

I repack my DI resin and get the refills through BRS along with sediment and carbon block. I pack my DI super tight and can get a few months out of it. I back flush each change out right when i install the new carts. that helps clear the dust from the carbon block and any that collect on the membrane at start up. My tank is relatively small compared to larger systems so obviously i would get more out of my RO than those with bigger tanks. it just works for me

Nice. My tank is also small vs most here (55gls or so with sump) but we use the Ro for drinking so I go through spectrapure .5 sediment filters and carbon blocks more than a semi used rodi for the hobby. I seen they have .3 sediment so I ordered a few.

Since I try to purchase the newest filters, I'm hunting that number rather than a visual color.

 

[reeftivo]

gotcha

i would rather just change when DI resin is exhausted. Because if I'm looking for 1 TDS to pop up and i start my drip with 0 tds, I may get TDS detected half way through the batch and need to dump it.

 

[chipmunkofdoom2]

I have a RO drinking system and I have it "T" off to my DI where I use for the hobby.

Currently I change carbon/sediment filters every 3 months or when the sediment is 100% dirty. DI gets replaced once I have 1ppm reading.

I feel I am changing RO filters more than needed.

At what PPM should I be replacing my drinking/RO filters?

This is not a bad filter change schedule, and is much better than what most people do. If you wanted to, however, you could refine it a bit further.

The main goal of the prefilters (the sediment filter and carbon blocks) is to protect the RO membrane. The sediment block protects the membrane from large particulate matter, and the carbon blocks protect the membrane from chlorine/chloramine. Chlorine will ruin a RO membrane in very short order, and chloramines are not great for the membrane either. To properly protect your RO membrane, you should be replacing the prefilters every 6 months on a regular schedule, regardless of what your final TDS is. You can replace your prefilters less frequently if you test intelligently.

To know when to replace the sediment filter, measure the pressure before and after the prefilters (but before the membrane). If there is a significant drop in pressure, at the very least, your sediment filter is clogged and needs to be replaced. If after replacing the sediment filter the pressure does not rise, the carbon blocks need to be replaced also. While less likely, it's possible that the carbon blocks can also plug with sediment and drop your system's pressure.

To know when to replace the carbon blocks, buy some chlorine/chloramine test strips. Test the brine/waste water from your RO membrane. If any chlorine/chloramine is detected, you must replace the carbon blocks. It's important to stop making water as soon as you see chlorine/chloramine breakthrough and not start again until you've replaced your carbon blocks. A relatively small amount of chlorine will ruin a RO membrane very quickly. If you're going to go this route, I would advise having fresh carbon blocks on hand so you can always replace them the moment you see chlorine/chloramine breakthrough.

Other than that, it sounds like you have a perfect replacement schedule. Just keep an eye on the RO membrane as well. Once the rejection rate drops below 96%, you may want to consider replacing that as well.

EDIT: after re-reading, I realized I never answered your actual question (at what ppm TDS you should replace RO/DI filters). The only filter you can really tell needs to be replaced by TDS is the DI resin. If it's over zero ppm, you should replace the DI resin. As stated, prefilters need to be replaced every 6 months on a regular schedule (sometimes more, sometimes less). RO membranes need to be replaced when the rejection rate drops, which can only be observed by testing water straight from the membrane.

 

[West1]

This is not a bad filter change schedule, and is much better than what most people do. If you wanted to, however, you could refine it a bit further.

The main goal of the prefilters (the sediment filter and carbon blocks) is to protect the RO membrane. The sediment block protects the membrane from large particulate matter, and the carbon blocks protect the membrane from chlorine/chloramine. Chlorine will ruin a RO membrane in very short order, and chloramines are not great for the membrane either. To properly protect your RO membrane, you should be replacing the prefilters every 6 months on a regular schedule, regardless of what your final TDS is. You can replace your prefilters less frequently if you test intelligently.

To know when to replace the sediment filter, measure the pressure before and after the prefilters (but before the membrane). If there is a significant drop in pressure, at the very least, your sediment filter is clogged and needs to be replaced. If after replacing the sediment filter the pressure does not rise, the carbon blocks need to be replaced also. While less likely, it's possible that the carbon blocks can also plug with sediment and drop your system's pressure.

To know when to replace the carbon blocks, buy some chlorine/chloramine test strips. Test the brine/waste water from your RO membrane. If any chlorine/chloramine is detected, you must replace the carbon blocks. It's important to stop making water as soon as you see chlorine/chloramine breakthrough and not start again until you've replaced your carbon blocks. A relatively small amount of chlorine will ruin a RO membrane very quickly. If you're going to go this route, I would advise having fresh carbon blocks on hand so you can always replace them the moment you see chlorine/chloramine breakthrough.

Other than that, it sounds like you have a perfect replacement schedule. Just keep an eye on the RO membrane as well. Once the rejection rate drops below 96%, you may want to consider replacing that as well.

EDIT: after re-reading, I realized I never answered your actual question (at what ppm TDS you should replace RO/DI filters). The only filter you can really tell needs to be replaced by TDS is the DI resin. If it's over zero ppm, you should replace the DI resin. As stated, prefilters need to be replaced every 6 months on a regular schedule (sometimes more, sometimes less). RO membranes need to be replaced when the rejection rate drops, which can only be observed by testing water straight from the membrane.

Awesome! I might try this and see if its worth continuing. My most recent .35 sediment filters were 20.99ea and if I remember correctly, that's a 3.00 increase from last years older model. I assume every year the newest sediment filter will continue to rise. With the improving product, Im not sure if spending more on smaller microns is worth it other. If I can get 2-3 more months out of pricier replacements, its worth the prices.

I am basically trying to justify my spending or keep to the cheaper stuff and replace every 3 months regardless of color, pressure etc

Link to sediment (also purchased the .5 carbon block somewhere in site)
http://spectrapure.com/FILTERS-MEMBRANES-RESIN/SEDIMENT-FILTER-CARTRIDGES

 

[chipmunkofdoom2]

Awesome! I might try this and see if its worth continuing. My most recent .35 sediment filters were 20.99ea and if I remember correctly, that's a 3.00 increase from last years older model. I assume every year the newest sediment filter will continue to rise. With the improving product, Im not sure if spending more on smaller microns is worth it other. If I can get 2-3 more months out of pricier replacements, its worth the prices.

I am basically trying to justify my spending or keep to the cheaper stuff and replace every 3 months regardless of color, pressure etc

Not a bad thing to consider at all. The Spectrapure small micron sediment filters are definitely high quality, but I agree, I often wonder how much "bang" you're getting for your buck. I just stick with the 5 micron sediment filter from BRS. The pore size is big for my liking, but it seems to work alright. I'm 7 - 8 months in on my current set of prefilters and I haven't needed to replace them yet.

I know a few reefers here buy the cheapest sediment filters and carbon blocks they can find and just replace them every month, and it works out pretty well for them. I use my RO system for drinking water as well, and I'm a little cautious to use no-name filters off Ebay when I'm going to be drinking the water that goes through them. But, it's an option nonetheless.

 

[Greybeard]

I'll change out sediment and (both) carbon blocks when the TDS after my membrane goes above 7 or so. It's usually around 3 or 4. That usually pushes it right back down. If it doesn't then a new membrane might be called for.

I move the 2nd stage DI cart into the 1st position when the one in the 1st position is used up, based on color change, and put a new one in the 2nd position. I generally check it when I'm making water for a water change, every 2 weeks.

I do not flush the membrane as regularly as I should. Know I should, never remember to do so.

 

[West1]

Not a bad thing to consider at all. The Spectrapure small micron sediment filters are definitely high quality, but I agree, I often wonder how much "bang" you're getting for your buck. I just stick with the 5 micron sediment filter from BRS. The pore size is big for my liking, but it seems to work alright. I'm 7 - 8 months in on my current set of prefilters and I haven't needed to replace them yet.

I know a few reefers here buy the cheapest sediment filters and carbon blocks they can find and just replace them every month, and it works out pretty well for them. I use my RO system for drinking water as well, and I'm a little cautious to use no-name filters off Ebay when I'm going to be drinking the water that goes through them. But, it's an option nonetheless.

Correct. The area it changes is because I use the RO portion for drinking and we are a family of 4 (the wife and kids drink water for a family of 9).

I'm understanding I need 3 of these, correct?
http://spectrapure.com/PARTS-SUPPLIES/PRESSURE-GAUGES-KITS/Pressure-Gauge-Kit-w-1-4in-push-fittings

Pre sediment
Pre carbon
after carbon

What would be a ball park drop in pressure to consider a replacement in filter, say 3lbs?

 

[Rookie_reefer_420]

@West1 Change all prefilters and check ppm’s and if they’re still high (like 15-20ppm’s coming out of the RO) then change the membranes as they’re done. Also flush out the ro before every use and the membranes will last much longer. Also watch for tds creep and run the RO part of the filter (you’ll need to add a valve and some tubing) only to get the higher tds water that’s been sitting in the unit from last use and get the ro tds back low before having the flow go thru your DI resin. Hope that helps

 

[West1]

I'll change out sediment and (both) carbon blocks when the TDS after my membrane goes above 7 or so. It's usually around 3 or 4. That usually pushes it right back down. If it doesn't then a new membrane might be called for.

I move the 2nd stage DI cart into the 1st position when the one in the 1st position is used up, based on color change, and put a new one in the 2nd position. I generally check it when I'm making water for a water change, every 2 weeks.

I do not flush the membrane as regularly as I should. Know I should, never remember to do so.

So 7 is your lucky number, now I'll need to check my number when I get home. I will assume time to change as they are currently pretty used.