When to change RO/DI filter materials?

Mightyfish · 04/26/2015, 02:20 AM

I bought a 4 stage RO/DI unit 7 months ago and i am wondering when do i know it is time to replace inside filter materials? My concern is if i dont change it before expiry then i may add water into tank that actually contains chlorine and kills my corals. Just used digital TDS meter to test and it is still showing zero reading.

serbusfish · 04/26/2015, 04:14 AM

Quote:

Originally Posted by Mightyfish

I bought a 4 stage RO/DI unit 7 months ago and i am wondering when do i know it is time to replace inside filter materials? My concern is if i dont change it before expiry then i may add water into tank that actually contains chlorine and kills my corals. Just used digital TDS meter to test and it is still showing zero reading.

For my RO unit the manufacturer recommends every 6 months, and the membrane every 2 - 3 years. Are you flushing the unit every 2 - 3 weeks? This will greatly increase the life of the membrane, but if I were you i'd consider changing the other filters (DI should be fine as you are still getting 0 TDS).

firemountain · 04/26/2015, 04:54 AM

Install an inline liquid filled pressure gauge after the cotton/carbon filters. As your carbon filters gets dirty and clogged, you will see a pressure loss that will give you an idea of how quickly your cartridges are being consumed.

Some install an extra one before the first stage as well..... To see their incoming water pressure......not totally necessary but helpful.

Mightyfish · 04/26/2015, 07:19 AM

Quote:

Originally Posted by serbusfish

For my RO unit the manufacturer recommends every 6 months, and the membrane every 2 - 3 years. Are you flushing the unit every 2 - 3 weeks? This will greatly increase the life of the membrane, but if I were you i'd consider changing the other filters (DI should be fine as you are still getting 0 TDS).

I flush it after every single use. Which section is the one that remove chlorine?

thegrun · 04/26/2015, 07:54 AM

As posted above without a good pressure gauge all you can do is guess as to when you really need to replace the pre-filters. The carbon filter removes chlorine, but if your water has chloramines in it you really need to use special catalytic carbon filters designed to remove chloramines. Several local reefers were having issues with their corals and when they tested their RO/DI water for chloramines found that regular carbon was not removing the chloramines. There are simple strip tests to determine if your water has chloramines in it after it has passed through your RO/DI unit.

04/26/2015, 02:20 AM	#1
Mightyfish Registered Member Join Date: Sep 2012 Posts: 280	When to change RO/DI filter materials? I bought a 4 stage RO/DI unit 7 months ago and i am wondering when do i know it is time to replace inside filter materials? My concern is if i dont change it before expiry then i may add water into tank that actually contains chlorine and kills my corals. Just used digital TDS meter to test and it is still showing zero reading.

04/26/2015, 04:54 AM	#3
firemountain Registered Member Join Date: Apr 2014 Location: Bergen County, NJ Posts: 1,033	Install an inline liquid filled pressure gauge after the cotton/carbon filters. As your carbon filters gets dirty and clogged, you will see a pressure loss that will give you an idea of how quickly your cartridges are being consumed. Some install an extra one before the first stage as well..... To see their incoming water pressure......not totally necessary but helpful. __________________ Eshopps RS100 sump, Eheim 1262 return,Kessil 360WE w/controller, Avast ATO w Litermeter 3, RO Regal 170sss Skimmer, Sicce XStream-e pumps /dc controlled, Spectrapure Dual Reactor Current Tank Info: 65g mixed reef

04/26/2015, 07:54 AM	#5
thegrun Registered Member Join Date: Dec 2008 Location: Garden Grove, Ca Posts: 17,023	As posted above without a good pressure gauge all you can do is guess as to when you really need to replace the pre-filters. The carbon filter removes chlorine, but if your water has chloramines in it you really need to use special catalytic carbon filters designed to remove chloramines. Several local reefers were having issues with their corals and when they tested their RO/DI water for chloramines found that regular carbon was not removing the chloramines. There are simple strip tests to determine if your water has chloramines in it after it has passed through your RO/DI unit.