75 GPD Reverse Osmosis Membrane - Dow Filmtec
Why does BRS recommend this?
DuPont is a leader when it comes to water treatment and filtration. Their 75 GPD membrane has a 99% rejection ratio, and most other membranes cannot make that same claim. Along with meeting NSF/ANSI standards the 75 GPD DuPont (formerly Dow Chemical) membrane is hands down the best membrane for our hobby.
Up to 99% rejection Dow membrane* - NSF certified
Compatible with all 10" RO Membrane Housings. Be sure to change the flow restrictor if you change the flow of your membrane.
FILMTEC reverse osmosis membrane elements for home drinking water are the industry's most reliable. Advanced membrane technology and automated fabrication allow these elements to deliver consistent performance that equipment suppliers, water treatment dealers, and residential customers can rely on. FILMTEC elements are shipped dry for convenient handling and long shelf-life. These elements are NSF/ANSI Standard 58 listed. Equipment suppliers can take advantage of FilmTec's Standard 58 listing and participation in the NSF Data Transfer Protocol to reduce costs for reduction claims for their systems.
- Rated at 50 psi
- Will purify about 20% more water than competitive elements rated at 60 psi
*DuPont Filmtec 75 GPD Membranes have a 96% - 99% typical stabilized salt rejection rate that can be reproduced through the following conditions;
- Source Water Pressure - 50 PSI / Membrane
- Source Water Temperature - 77°F
- Source Water TDS - 250ppm Softened Tap Water
- Recovery - 15%
- Minimum Salt Rejection - 96%
For more info on DuPont Filmtec BW60-1812-75 Membrane - Click Here
There are many reasons why you might see poor performance from an RO membrane. It can be as simple as a seasonable drop in water pressure or temperature. Other seasonal fluctuations like the amount and type of disinfectant used by your municipal water treatment facility (chlorine vs chloramine) can also be an issue. Both chlorine and chloramine can degrade a membrane so if your carbon block(s) are exhausted and allowing them through it can lead to a drop in performance. Free and total chlorine test strips are a great way of monitoring the performance of your carbon blocks.
We recommend using the Universal carbon blocks due to their increased capacity and ability to treat chloramines provided you use two of them.
It is possible that the membrane housing is the issue but the gasket on the membrane its self is a more common problem. You can try removing and reseating the membrane to ensure there is a good seal there.
Once you have ruled out these other potential issues you can try a new housing but based on experience it is an unlikely the source of your issue.
I hope this helps! Please let us know if you have any further questions.
Great question! This is our recommended option as it provides a slightly higher rejection rate for better performance, however many people choose the extra water production making the 100gpd the most popular. If you have any other questions don't hesitate to ask. Take care!
Have a great day!
Generally it's recommended to flush the first 10 gallons or so as this initial product water contains higher TDS water due to the preservatives on the membrane and the re-hydration period. After this, it's considered to be fine to start collecting water for use. The information on 24 hour operation pertains to reaching full membrane hydration and optimal performance, however the water can be collected before this time. Usually you can expect to reach above 80% of max performance within a few hours of operation.
Hope this helps!
A new membrane can be stored for quite a bit of time. The manufacturer puts a preservative on the surface of the membrane which can keep good for quite some time (2+ years). That is they recommend discarding any water produced for the first hour or two when it is first installed. Storage for the membrane should be kept in a cool dry place with a steady temperature.
Ideally the membrane will last around 2 years. You will be able to see with a TDS meter on the IN section. The ro should reduce around 99% (with a single membrane) and bring your TDS on the In to around 0-10. If on the single membrane it is higher than 10 after running the unit you will want to consider a replacement. With the water saver version dual membrane the IN TDS will be a little bit higher closer to 5-15 TDS. Feel free to let us know if you have any further questions!
These membranes are recommended for 50-75 PSI the maximum mount we typically see during flushing is 80 with no negative effect. Feel free to let us know if you have any further questions!
We have found using the system after Water Softener will improve the life of the unit and membrane. This will not cause the unit to clog any faster than normal. Feel free to let us know if you have any further questions!
Most membranes will be a universal physical size and work in all units. You will need to make sure the GPD rating is the same. If they are not the same you will need to change the flow restrictor on the waste water line to a 75 GPD flow restrictor. Feel free to let us know if you have any further questions!
The RO membrane will remove around 97-90% of the TDS for a good range after flushing this should be typically between 000-010 however it can be higher with poor source water quality. Feel free to let us know if you have any further questions!
Overall they will function on the same process of TFC however certain membrane which are High Silica can last longer due to the negative effect of silica. The difference between the membrane is not that one will remove more or less rather the life span of the membrane for a specific application. Feel free to let us know if you have any further questions!
The unit can handle up to 80psi without issue and it does perform better at higher water pressure. I would go ahead and run it at the 80psi, there isn't any reason not to and performance will only go up.
The membranes last quite a long time, typically 3-5 years though if you treat them well (vigilant on changing your pre-filters on time, etc) they can last even longer.
Membranes are a standard size so they will fit in any unit. Just make sure that if you change the speed of the membrane you also change the size of your flow restrictor to match.
That sounds pretty typical. It is higher at first because of tds creep and will lower as it runs. Non-exhausted DI resin should give you 0 TDS coming out. The membrane itself will typically last 3-5 years, sometimes even much longer. DI resin doesn't really have a "normal" as it is completely dependent on your source water. Monitor the TDS and when it begins to go above 0 then it is time to change the resin. We use a color changing DI resin so this should also coincide with the resin turning from a dark blue/black color to a gold/yellow color.
If you change the size of the membrane without changing the flow restrictor to the proper size your unit will have the incorrect amount of waste water. It will either have too little water which would damage the membrane or too much water, which is just a waste of water (and could decrease pressure). The housings for the membranes themselves are universal. The membrane is what changes the output, though there are some other factors such as water pressure and temperature that do as well.