New filters RO/DI

[Opus]

Update I replaced all of my filters except the RO membranes they are about 2 years old. I changed how my Inline filter reads, so now I checked my source water IN and between the RO membrane and the DI filters.
So now 360 source water and 10 PPM out of the RO membranes, does this sound about right? I checked my DI with a handheld and it reads 0 PPM.

That is a good number. You are sitting at 97.5% so not bad. It is well within the manufacturers spec of 95% rejection rate. So now it depends on if you are OK with that number. I have the 99% rejection membrane and my tap is over 400 and my tds after the membrane is 4. This number effects how long your DI will last. My 4 will get me around 1100 gallons of 0 tds water from a regular sized DI filter. Your 10 tds will get you around 440 gallons of 0 tds water.

 

[flyfisher2]

That sounds good. And hopefully it'll stay that way. Just monitor what's coming out of your membrane from time to time. I have an ongoing issue with burning through membranes but I think we've narrowed it down to heat and possibly high chlorine or a faulty Membrane housing. I have a thread going as well. Good luck with yours. Eating Up RO Membranes

 

[Blue Ring Octopus]

Thanks again, I have purchased two more expensive RO membranes from MD while they were on sale, so I will change them but I will see how much I can get out of these.

 

[Blue Ring Octopus]

So I checked my system and now I have 500 tds at the source and 12 coming out of my DI, everything is new except https://spectrapure.com/collections...us-99-rejection-ro-membrane-90gpd-mem-sp-0090, so I bought two of these so does it mean that I replace these now?

My hand held HMDigitial TDS-3 that I purchased from a sponsor here that does water machines so I am comfortable that it is not a counterfeit, it is reading 1 - 2 TDS.

This is one the that states that it is 12 after the DI, https://www.bulkreefsupply.com/deluxe-dual-inline-tds-meter-dm-2-hm-digital.html.
So which one to trust?

 

[flyfisher2]

There are formulas to determine the rejection rate you can expect from your membrane and the DI should be bringing you down to zero or very close to zero regardless of what makes it through the membrane. Just remember that if that number is relatively high you'd be burning through DI quickly. If I were you I'd be checking what your TDS is reading after the membrane (before your DI).

 

[Blue Ring Octopus]

Ok thanks I will buy another tester for that.

 

[Spare time]

https://www.bulkreefsupply.com/content/post/howto-know-when-to-change-your-rodi-filters

 

[Blue Ring Octopus]

I purchased another tester for my system so now one checks the water coming into the system and then before the Di and and after the DI so my reads are 473,10 and 0.

 

[banger32]

You said your pressure gauge is broke is it broke or just clogged? I thought mine was broke also but really it was just clogged

 

[Blue Ring Octopus]

I tried cleaning it and it did not make a difference, what did you do to clean yours?