ro and ro/di

[DirtyDeeds]

will ro work for saltwater tanks bez its much cheaper

or do i need a ro/di

[75gsalt]

RO will work just fine but the RO/DI is better, since it will have near 0 TDS

[Lightsluvr]

RO is fine for FOWLR, okay for most softies. not so good for SPS coral.

Unwanted TDS in RO water can be cumulative in your tank...

LL

[Randy Holmes-Farley]

RO is potentially unsuitable if your water supply uses chloramine, because the RO effluent will have lots of ammonia in it.

The other thing that gets through it fairly easily is silicate, so depending on what amount of silicate is in the tap water, that may or may not be a concern.

Otherwise, it is only a concern if your water is among the highest around for copper (which comes from your own pipes.

I detail what the various stages do here:

Reverse Osmosis/Deionization Systems to Purify Tap Water for Reef Aquaria
http://reefkeeping.com/issues/2005-05/rhf/index.htm

[DirtyDeeds]

bez my bro just bought me a ro unit. should i go return it and get a rodi unit?.

[DirtyDeeds]

all iam keep are soft coral like mushrrom and kenya tree zothlin and frogspawn should it be fine?

[Lightsluvr]

bez my bro just bought me a ro unit. should i go return it and get a rodi unit?.

Add a DI stage to it... check Air Water & Ice (a RC sponsor)

LL