I am looking at buying a Reef tank and currently do not have an Ro/Di Unit....the tank will be 65 gal with 20g fuge and 20g sump so I am guessing about 1 g a day in evap....Does anyone know of a good place to purchase an inexpensive unit...or have a old one they are wanting to get rid of??? also I heard about a portable style that hooks right up to your sink faucet....anyone have any experience with this?  I can put it under the kitchen sink bit don't really have any other place for it.  I will have to haul water upstairs to the tank which will not be fun....the bathroom upstairs is is to small i think to install a unit so the portable system would be nice!!! I found this online for $109

So this one for $79 would work out for me then???

PREMIER AQUARIUM REEF REVERSE OSMOSIS /DI WATER FILTER SYSTEMS

THIS IS A 4 STAGE REVERSE OSMOSIS DESIGN FOR YOUR AQUARIUM REEF.

THIS SYSTEMS COMES WITH THE FOLLOWING:

*ALL CLEAR FILTER HOUSING 

*WHITE MEMBRANE HOUSING

*METAL BRACKET FOR TRIPLE HOUSING 10" CLEAR

1ST STAGE 1 MICRON SEDIMENT FILTER

2ND STAGE 1 MICRON CARBON BLOCK FILTER

3RD STAGE 50 GPD REVERSE OSMOSIS MEMBRANE

4TH STAGE DI FILTER WITH COLOR INDICATOR REFILLABLE CARTRIDGE

ALL QUICK CONNECT FITTING

CHECK VALVE

ALL COLOR CODE TUBE FOR EASY INSTALLATION

FEED WATER CONNECTION OPTIONS:

1. UNDER SINK CONNECTION (FEED WATER ADAPTER AND SADDLE DRAIN VALVE)

2. GARDEN HOSE CONNECTOR

3. FAUCET ADAPTER

ASK FOR ONE OF THESE OPTION AT CHECK OUT OR WILL SEND OPTION 1

ALL FILTERS ARE STANDARD INDUSTRY SIZE FOR 10" HOUSING

2.5" X 9.75"

WHAT OPTION SHOULD I PICK #1,2,3 ????   Does # 3 mean it can hook to any sink and then be put away when not in use ( portable ) ???  

http://stores.ebay.com/PREMIER-WATER-SYSTEMS

sterling18 wrote: Shhhh, don't tell anyone but I use TAP water.

Good thing this isn't Reef Central, you'd probably get banned for an inflammatory statement like that.

It depends on who you ask. Some will say that nothing will happen, others will say that every fairy, puppy, and cute little clownfish on the planet will be instantly destroyed.

As with most things, the truth lies somewhere in between. There will most likely be chlorine in your tap water, letting it sit for a day or so will get rid of that. Beyond chlorine, there are different things that come in the tap water and that your municipality adds to your water. Find your city's website and try to determine what is in your water. There's a chance that the elements in your water can be managed with healthy macroalgae and good biodiversity. But it's also possible there is copper or other impurities in your water that will make things very difficult for your reef.

I prefer using RO or RODI water as it eliminates variables, I know the elements and supplements that I add are the only things getting into my tank. But many healthy reef tanks are done with tap water.

I just started using RO purchased from LFS. when I started using it for top off an entire clump of macro turned white and got eaten by my CUC. I don't know if it was a direct connection but it did happen at the same time. I find when I use tap water in Bountiful I don't need to dose Alk. I would suggest if you plan on using tap to get a bunch of different test kits and watch your parrameters. where you live you may not have to worry about it. So like others said check your local water.

I test for Alk, Ca, Mg, and phosphates. Then I have a dip strip just to get a base line for nitrates, nitrites, and PH.