Since a salt water tank needs to stabilize first for about at least 4 months before you can put some corals on it, using an RO
at first is okay which is available in your nearest grocery store at 25 cents/gal
. You can have fish only with live rock until your tank is ready for corals. You can then have time to get ready to install an RO
. The best place for it is under your kitchen sink. You need a 3/8 in gate valve from your water supply to attach the plastic tubing and you need to provide a drain for the waste by product. I started with an RO
with faucet included and just added the "ad on" DI
later. I have a pressurized reservoir tank of about 1.5 gal
and I collect it whenever I can until i have about 20 gal
per week for my partial water change.