Most effective RODI addon stage for chloramines

[R_MC]

Hi all,

 

I currently run a pretty standard 5 stage RODI (Physical / Carbon / Carbon / RO / DI). This setup used to last about a year between refills in my old apartment.

 

I replaced the filters ~6 months ago and produce 5 gallons of filtered and ~20 gallons of RO water per week (60 in the summer when I use it for hydroponics). My tap has 400ppm TDS (Cambridge city water - yikes...). Recently, I noticed that I was getting algae growth and so I checked my TDS out - it had already climbed to 200ppm. I assume this means that my RO filter is shot, and that obviously I need to replace the others as well.

 

So... I'm looking for 2 recommendations.

 

1. What is the best carbon block for chloramines?
2. Is there an effective "addon" stage that I could use to increase the life of my RO membrane?

By Addon stage, I'm thinking of a single 20"x4.5" chamber for an additional carbon block either before or after my first 3 stages. Or a dual physical / carbon of the same size that would be used before my 5 stage RODI.

 

Thanks,

Rob

[seabass]

For a 5 stage unit, I'd get http://spectrapure.com/FILTERS-MEMBRANES-RESIN/FILTER-REPLACEMENT-KITS/Standard-0.5-Micron-Pre-Filter-Replacement-Kit

and http://spectrapure.com/FILTERS-MEMBRANES-RESIN/FILTER-REPLACEMENT-KITS/MaxCap-MAX-KIT-RO-Membrane-DI-Cartridge-Upgrade-Kit-for-MaxCap-RODI-Systems

It will handle chloramines as well.

[MainelyReefer]

Cambridge MA? I own a water filtration business in Exeter NH and was having similar problems and installed a 10x54 self back washing fleck 5600 control head granulated acid wash carbon filter and haven't had the issues since. It's overkill most likely but now even my shower doesn't smell like chlorine huge plus! I also know of the big blue prefilters you are talking about, my business manufactures whole house reverse osmosis units and we use a 2.5x20 5 micron polyfiber spun and a carbon block before a 4x40 membrane, never install these in city water though only wells so maybe the 10x54 is the best bet but that's $1600 installed haha

[Water Dog]

20# size 4 Chlorplus block... Here's a lengthy discussion on it on RC.

 

http://www.reefcentral.com/forums/showthread.php?t=2483520