4 or 5 stages; question about RO/DI

[Crustman]

I just ordered the BRS 4 stage unit. I looked at others with 5 stages at 75 gallons/ day but the best value with shipping charges was the BRS one; just my opinion. What is the 5th stage for? Is it a cloramine filter. I think it is a carbon block. Can I add it later to the basic unit. I have a TDS meter and my tap water is 40 ppm TDS. Will the unit produce 0 TDS and be optimal for my reef aquarium. Thanks,

[ahenson]

You are lucky your tds is already really low. My well water was 4-500 This should last a long time

[coral_killer37]

I have the brs 5 stage. the 5th stage is the DI filter and it is important for phosphate and silicate removal. The first 4 stages remove metals, chlorine and caustic from the water.

[ahenson]

http://www.bulkreefsupply.com/store/75-gpd-ro-di-4-stage-economy-system.html
His also has a DI Does yours just have a second DI

[frgrasso]

I have a 4 stage Kent maxxima and my Tds is 0-1 at all times

[Denbf58]

i have brs 5 stage plus my tds before the di around 5 then 0 after di and that is with a tap water aporx.150 200 tds it also depends on your water pressure the closer to 90 psi the better save up and add the DI chamber when you can

[jeff@zina.com]

What is the 5th stage for?

The comparison chart on the item page for what you bought shows the differences: http://www.bulkreefsupply.com/store/75-gpd-ro-di-4-stage-economy-system.html. The missing filter in your system is a sub micron carbon block for chloramines. If you don't have them, you don't need this stage.

Jeff

[Crustman]

Thanks everyone. I think I will be fine with the unit.