switching to RO/DI

[derek_setter]

I use tap water.... I Know I KNOW!... but ia m getting an ro unit. I am getting one of the systems off of ebay (unless someb ody can give me a better deal). I have a 75 gal. tank and a 15 gal. tank. I have been using tap water on b0oth of them for quite a while... I dont' know exactly what all is in my water, but i know right now it is fine... i have never had any algea problems or problems with invertabrate. When i get the ro unit, should i change out the watetr from my tanks, and i mean ALL of it... another problem i have is that when i try to chagne the water in the tank, i can't even take out a full gallon withought adding all of it back in, becuase the water in the sump is set to be so low (because if the pwoer goes out , it would overflow otherwise) that the pump runs dry.. what can i do?

[NicoleC]

Turn off the pump while doing a water change.

I'd just start topping off and using the RO for water changes. It helps to have some 5g buckets with lids around so you can run the RO unit and stock up for the week instead waiting for water everytime you want to top off.

[cellexjohn]

You must have a problem with back feeding through the return lines, right? you need to drill a small hole in your return line just below water level. that will break the siphon as soon as the water level reaches the hole. OR... you have a very small sump. for that, I would have to recomed a bigger sump if you want to run one. NicoleC make a really good point if you are not turning off your pump when doing water changes.

Maybe you are removing water from the sump and don't have enough there to do a water change with? I usually just kill the main pump and shut the ball valve on the return line to keep the main tank from draining too much and remove most of my water from the display tank. I make sure to keep all corals atleast a few inches from the the water surface...

Oh, don't worry about changing all the water. Just do water changes with the RO/DI water from now on. I use a RO/DI unit from one of our sponsers Aquatic Reef Systems (http://aquaticreefsystems.com) they have top notch equipment and are very helpful on the phone if you require any assistance. Be sure to to call your water supplier if in the city and find out if they use chlorine or chloramine for treatment as it will affect they filters you will require.

WOW, that turned out to be a rather long post. :)

John