kitch40

ASAP IMO, albeit slowly.

Yup, you won't want to do it all at once. If you are in a hurry, perhaps do a 10-15% water change every other day or so for a week. After that, you can do weekly or every other week as a maintenance. I'm assuming your tank is suffering from not using RO/DI water, so pay attention to your animals and use that to be your judge on how often you need to be doing water changes. As things improve, you can adjust the water change schedule.

Thank you , actually my tap water is good and the fish and corals are all good but my hair algae is bothersome and I am trying to get 0 phosphate. The tapwater here seems to be .5 and the tank is .5 phos. so with the new water hopefully that will go down.
P.S. thnks to Melev's reef for a great deal on the filter.

If you have been maintaining the tank with tap water and everything is in good shape why get in a rush. Just do your regular water changes and top off with the rodi and it will start falling. Dropping po4 to fast is as bad as it being high.

If you want to get it done in a couple days, you can do a very big very long water changes, put the fresh SW in your ATO reservoir and use an airline on a siphon to remove water from your tank, with this method I can change out about 5gal in about an hour. It is my preferred method for water changes because it reduces the chance of drastic change. This being said the most I would ever change out is ~30% daily

this being said its sort of a waste of salt just to replace your water, I'd just keep on with your regular changes in a couple weeks it will be switched over

Thanks to all!!!

And of course, you can use Phosphate Control to nuke the PO4 in your tank, catching it in a filter sock (the fuzzy kind, not mesh) or let your skimmer export it overnight.