RO/DI filter question

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Aquarium Advice Apprentice
Dec 16, 2008
I am newbie and my tank 75 galon SW reef, it really need RO/DI filter?

Thanks for your helping
Yes, yes, ro/di filter will filter tap water to put into your sw tank. Initially it's a sizeable investment....but very well, worth it.

Ok you SW guru's.....chime in here.
I recommend to say yes! It would be the best investment you could ever give your reef and your fish. I would element all the nasty chemicals that are in Tap water and Well water depending on what your on now. and It will diffinetly help get rid of any algae issue you are having with your tank. I picked up this RO/DI unit and it work great.
Does it really need one? No. There are plenty of folks that have successful tanks using dechlorinated tap water.

BUT... in my opinion, if you're going to keep corals, you should have one. Consistancy is the key to success in this hobby, and without a consistant water supply that is also pure, you really don't know what you're putting in your tank. With a RO/DI unit, you have consistantly pure water that you're starting with, and YOU (and your salt manufacturer!) control what goes in it.
Agreed, agreed , agreed. Short of a refract it's the best investment you could make
So, this unit connect to the sump from the water out put, that correct?
Highly depends on what your tap puts out, which you can test. If you want to be safe then purchase one. I've always used tap, for 10+yrs without problems and only switching to ro/di because of personal preference and not necessity. All systems can either be hooked up directly under the sink (main water line) for automatic reservoir filling (or not) or using a standard aerator adaptor for the faucet, hose, etc. Ro/di's should have the fill line running to a reservoir of some sort and not your aquarium.
Most people set their unit up in a location that they can fill containers with pure fresh water. I have mine set next to the floor drain in my basement which is only a few feet from my tank. I fill a 32g trashcan when doing a PWC. I mix my salt in the trashcan with a 660gph pump and after a couple days of mixing I do my water change. I also use my RO/DI unit for top off from evaporation in my reef.
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