2 Dumb Questions re: RO/DI

**Masala** · 08-30-2008, 06:16 PM

1) For those of you that have your own RO/DI water units at home, where are they mounted?

2) If I buy RO water at a store, do I need to add any of my usual stuff to it like Amquel and/or NovAqua?

Total rookie questions, I know, but I just don't want to make any stupid assumptions (about #2) and end up killing my entire tank....

**cocoa_pleco** · 08-30-2008, 06:18 PM

1. Cant help you there, i buy it in jugs

2. If this is freshwater, you need to mix half with tapwater, so yes you need conditioner. RO straight for saltwater is safe, but not freshwater. its too pure for freshwater

**CAllain** · 08-30-2008, 06:28 PM

Can't help with 1, but for 2...

For freshwater, some stores will add minerals to the RO for you. In this case you won't need conditioner. However, if they don't, or if you prefer to mix with your tap water for more control, you will still need to use conditioner as cocoa said.

**kaybee** · 08-30-2008, 09:32 PM

1) I don't have mine permanently mounted.

2). Typically, no dechlorination products are necessary.

I say 'typically' because it depends how their RO unit is configured. If there is one or more carbon blocks prior to the membrane or if it is RO/DI water, it should be fine. That's how mine is set up (carbon prior to the membrane and DI after it) and no dechlorinization is necessary for the end product (RO/DI water).

If the configuration is pre-sediment filter and membrane only, then you might want to test it for chlorine content. From what I understand chlorine damages the membrane so this should not be the configuration used.

p.s., good questions, actually.

**MrDrums** · 08-31-2008, 02:10 PM

What is the reason that you need it? What is your tap water like? I have well water, treated, and I just add that directly to tank in a water change, then throw in stress coat / stress zyme and occasionally some aquarium salt. I even did that when I was on city water with no problems. Saves money if you can use tap water.

**Masala** · 08-31-2008, 04:03 PM

Originally Posted by MrDrums

What is the reason that you need it?

I've been trying to get my hardness down (GH >12, KH ~8ish) so that I can one day buy a discus, but I keep seeing that the minimum they need is 55gal. Since I have a 29gal, perhaps that's not a worthy endeavor to pursue anymore.

You are right, though - I could certainly save money if I just use my tap water and be happy with the fish I *can* keep...

**MrDrums** · 08-31-2008, 04:18 PM

I have never kept discus - they are beautiful, but from what I understand they require certain specific water parameters. In my opinion, though, the less you mess with the water chemistry the better off your fish (and you) will be. Best of luck with your fish, and with your discus if you decide to go that route!

**ILuvMyGoldBarb** · 08-31-2008, 05:02 PM

1: can't help you as I don't have one.

2: As has already been stated, RO/DI does not need any kind of dechlorinator since the RO membranes and the DI filters generally remove chlorine and chloramine. However, if using it for freshwater you do need to reconsitute the RO/DI with something. Some use tapwater, I'm not a huge fan of this since you can't control what is being put back in the water. Personally I prefer the products out there that are available. Here are just a couple.
Discus - Seachem Discus Buffer and Discus Trace
Planted Tanks - Seachem's Equalibrium
Cichlids - Any of the appropriate buffers from Seachem work well.
Marine - Any good line of trace elements and buffers are good. Many like the Aquavitro line or Dr. Brightwell's line.